Oral-History:Herbert Weiss

About Herbert G. Weiss

Weiss was an MIT undergraduate in electrical engineering who began work on MIT’s Instrument Landing Program (ILP) in the late 1930s, spending some time working at Tuxedo Park too. He came into the MIT Rad Lab about April 1941 and started working in the receiver group under Lew Turner. His greatest contribution was to make a stable receiver that was lightweight—he got the weight down from 50 pounds to ounces. Later in the war he started doing systems programs work, integrating receivers, etc., into functioning systems. He helped assemble an American knock-off of the British Oboe navigational system, then spent 1943-44 in England installing American Oboes into bombers. When he returned to the US he worked on Project Cadillac, the AEW predecessor. 1945-48 he spent at Los Alamos improving the mechanical engineering of the a-bomb. 1948-51 he worked at Raytheon doing computer work. Starting in 1951 he joined Project Charles, building a continental air defense network.

About the Interview

Herbert G. Weiss: An Interview conducted by John Bryant, IEEE History Center, 13 June 1991

Interview # 099 for the IEEE History Center, The Institute of Electrical and Electronics Engineers, Inc. and Rutgers, The State University of New Jersey

Copyright Statement

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It is recommended that this oral history be cited as follows:

Herbert G. Weiss, an oral history conducted in 1991 by John Bryant, IEEE History Center, Rutgers University, New Brunswick, NJ, USA.

Interview

Interview: Herbert G. Weiss
Interviewer: John Bryant
Date: 13 June 1991
Location: Cambridge, Massachusetts

Family and Educational Background

Bryant:

I'm John Bryant. This is the 13th of June 1991. I'm interviewing Herbert G. Weiss for the Oral History Project of IEEE, celebrating the 50th anniversary of MIT Radiation Lab. Herb, I'd like to start by asking for some background. Your family, your father perhaps, or why you chose to be an engineer.

Weiss:

Okay. I was born in New Jersey, and my first acquaintance with electronics was about the age of 12 or 13. We had a battery-operated radio, which didn't work, and I asked around about what do we do about it. They referred me to a man two blocks away, who was a radio ham it turned out. So I carried this monster with the big horn and, I guess, the dog sitting on the speaker to his house. We went down in the basement, and I was just fascinated. I was hooked right then and there. A year later I became a radio ham at the age of 13, 14 and literally have been in the field ever since, until I retired. I was fortunate enough to go to MIT as an undergraduate, and most of the people I ran into of that vintage didn't really have a hands-on feeling for electronics. By the time I got to MIT, I had built all kinds of things, including a TV set. Then it turned out that NBC was just trying to get their TV set on the air in New York on top of the Empire State Building.

Bryant:

That was an electronic television.

Weiss:

All I could look at was a picture of an Indian on the tube they had for target display. They had no programming going on in 1937, 1938. They were just getting the gear up and running. They may have an hour at night or something, but it was really pretty primitive. I found myself at MIT as an undergraduate in EE, of course, and became very aware of the fact that people were teaching courses pretty much out of a book. They had a reasonable familiarity, but they couldn't fix a radio. If something had to be repaired or modified, I was usually the guy in the laboratory that got called on to fix the gadgetry. It was all vacuum tubes and big clumsy stuff, and I felt very much at home with that.

It turned out MIT had a contract with the CAA to do work on instrument landing. Professors Barrow, Hall, Bowles, all at MIT, were in the middle of that program. Frank Lewis and Don Kerr were principal participants. As a junior I joined that group to build equipment. I was asked to work on the receiver electronics for what was then called "microwave." It turned out to be about 200 MHz. But we were using acorn tubes and doorknob tubes. I was doing that nights and part time as a student and was earning 36 cents an hour. They had a student aid program then that was federally financed, and I ended spend many nights, weekends, and summers in the laboratory. During my senior year I was working there a lot of the time. We had a pretty active group working on high-frequency electronics. There were some very bright people, and I was a neophyte in the sense that I was 18 years old or something like that, and I was thrust in the middle of people such as Barrow, who were really preeminent people in the field.

One day in the laboratory, without any real warning, the door opened, and Professor Bowles led a delegation into the laboratory and walked around and looked at the benches. They looked at what we were doing, and we explained everything. It turned out to be the committee that was sent over from England to examine what was going on in various places.

Recruitment to Radiation Lab

Bryant:

Was that the Tizard Mission?

Weiss:

That was the Tizard Mission. It was all focused on trying to get a radar laboratory started in the U.S. We didn't hear any more of them, at least at my level. It wasn't more than months later when it was quite evident there was something going on at MIT in electronics, but I was excluded from it. I was signed on to work on the Instrument Landing Program, and a few of the people got dragged out. One or two others were left to wrap up all the paperwork, make the stuff finally work, and finish the test program. So I ended up getting into the Laboratory probably four or six months after it got started.

Bryant:

Well, it says April '41. Does that sound right?

Receiver Group

Weiss:

Could be. My memory for dates is pretty poor. Meantime, though, we were working with the klystrons that the Varian brothers and Bill Hansen brought to MIT as part of the Landing Program. They were set up at Logan Airport, which was then a gravel field. We had some "microwave" beams that were directed up the runway-landing path normally used by commercial airplanes. Commercial airplanes in those days were an Eastern Airlines Ford trimotor that came in from Newark about twice a day and a couple of DC-3s, I guess. In any event, I ended up in that activity and was very much in the middle of klystrons. We built the first "microwave" triple conversion super heterodyne, which turned out to be at 200 MHz, but that was our definition of microwave at that time. When I moved into Radiation Laboratory a few months later, I ended up in the receiver group with Lew Turner as division head. I was in the receiver group with people such as P.R. Bell, Van Voorhis, Bill Breazeale, I have to think of them. Jim Lawson was there for a while.

Bryant:

The receiver group had the indicators and receivers both?

Weiss:

That's correct. I think that's right.

Bryant:

Under Turner and Haworth, for a while.

Oboe Project and England

Weiss:

Okay. My specialty was a carry-over directly from what I was doing in the Instrument Landing Program: building IF amplifier strips and detectors, essentially from the RF back to the back end of the receiver. I must have spent a year and a half, two years there. In the meantime, I was dragged into various systems programs that were underway, which used the hand-made receivers that were delivered by our laboratory into field test equipment up on the roof and various field sites. Frequently they didn't work quite right, and so the "experts" from the receiver group were called in to fix them or called down to some test site nearby to fix it. So it wasn't very long before I was in the sort of system type of problems rather than receiver problems because the whole integrated package had to work. The Laboratory decided to get into the Oboe project, a precision navigation system. The British had developed Oboe, which worked very well at the longer wavelengths, and it was highly successful as a low-frequency system. They were worried about countermeasures.

Bryant:

Oboe is a navigational system?

Weiss:

Oboe is a navigational system based on ranging from two ground stations. The two ground stations, known as a cat and a mouse by the British. The range to the target (usually in the Ruhr) would be determined from each ground station to. Essentially a beacon transponder was put on a high-flying (28000') airplane, which at that time was a Mosquito, and it was directed on a circular arc centered on one of the stations; there was a range, gate set up at the designated range which automatically modulated the transmitter. This pilot would listen to his headphones, and he would have a modulated dot-dash signal that would tell him to go right or go left. In the meantime, the other station was also tracking the same beacon transponder, interrogating the transponder; at the designated release point, which was computed based upon the speed and other parameters. At the release point the pilot would drop colored flares. In the meantime the RAF heavy bombers (later on, on the B-17s and B-24s) would converge on that spot and release their bomb loads. The people on this special team, both RAF and VS, were called the "Pathfinders." The operations were based at an RAF airfield called Alcanbury, about 50 miles northeast of London. Our technical group was the first VS contingent at TRE (Gt. Malvern). I ended up being asked to get six experimental Oboe systems assembled. Other lab groups supplied the transmitters, modulators, and antennas. When the time came to bring the equipment to England to put it in the Mosquito aircraft, I was drafted to be the systems man.

Bryant:

How did that compare with the British Oboe system?

Weiss:

It was really a derivative of the 200 MHz British system almost all the way, except it was at, I think, X-band. I could be wrong about that. It might have been S. But it was the same kind of electronics, the same ground stations physically.

Bryant:

But it was microwave?

Weiss:

It was microwave.

Bryant:

Two hundred megahertz? One and a half meters?

Weiss:

Right. It was the microwave equivalent.

Bryant:

What was the range of the first one to go?

Weiss:

It was limited by line of sight. Mosquitoes were chosen because they could fly very high. With luck they could make 30,000 feet. The heavy bombers were much more constrained, and with their payloads they were down to 20,000 feet or something of that sort. Our maximum operating range was about 250 miles.

Bryant:

That would be beyond line of sight.

Weiss:

Yes, but we had extra signal strength because we had a one-way radar beacon. It proved to be a very successful system. In fact, with the weather being so lousy, there were many days that the only thing that flew were the Oboe-led Pathfinders followed by the heavy-bomber fleet. The British were very, very clever. I had my eyes opened many times by the things they were doing. For instance, if you take the Ruhr, which is roughly two hundred and some odd miles from the ground stations on the south coast of England and if you flipped the target ranges over the base line between the ground sites, you end up in Scotland. So the British Operations people would pick a target, usually the day before the range from each ground station was determined, and the ballistics people figured the drop point. We had a small trailer truck, which would be up in Scotland, and we'd park it as close as we could to the designated target point, the flip-over point. The same Mosquito, with the same equipment, same pilot, would do an afternoon flight. The IF bandwidth was narrow and we were trying to do leading-edge ranging and trying to get accuracy down to 50 or 100 feet — numbers that were really impossible, as they were influenced by the signal noise and the bandwidth. Some receivers had the IFs tuned a little different than others, so it was necessary to calibrate each system individually.

Bryant:

This was done in the equivalent of about 2/10ths of a microsecond pulse.

Weiss:

Right. We were using long pulses, and were doing leading edge ranging.

Bryant:

But you should have had a bandwidth of several megahertz.

Weiss:

We probably had a bandwidth of 2 MHz. Because we had vacuum tube IFs amplifiers, it was difficult to achieve the desirable bandwidth. So the range was very much a function of signal strength. Each equipment was handmade, and the performance was always a little different. One always tuned up a little different. The antennas were never consistent.

Bryant:

What time period would that have been?

Weiss:

I think I arrived in England with the gear in 44 because when I left England after about a year, it was just about the week of the invasion of Normandy. There were four or six of us in the laboratory at TRE in Great Malvern, working not only on Oboe but also on several other projects. I was the Oboe man. I worked very closely with F.E. Jones, who became president of either Plessy or GEC.

Bryant:

One of the major British electronic firms.

Weiss:

In any event, he was a British project leader on the technical side, and I worked with him as the American counterpart team. I won't dwell on Oboe too much. It turned out to be very successful. It got used by the Eight and Fifth Air Force as soon as we had enough gear to install on the B-17s, B-24s, and B25s, the lead planes in a group got equipped. The follow-on groups would drop bombs based on their flare drops. It was impressive, as a young kid at that time (about 24), to be involved with the airplane that was leading the Air Force. After we did our timing test runs, you could start hearing the bombers warm up. The whole sky was black with them. I mean all heavy U.S. and R.A.F. bombers were in the air flying on this one Pathfinder plane that we were rushing around with in the afternoon. Once in a while, if the Oboe malfunctioned, they had to scrub a precision mission and revert to area saturation bombing, which was relatively ineffective.

The British operations people had all kinds of interesting calibration techniques. They would occasionally have a tough time getting feedback of exactly where the Pathfinder bombs were released. We had some biases in the system, and we really wanted to get them out. At one time they picked a target, which was a spot between a hospital and an ancient cathedral in some city in Germany. They tried real hard to drop a single bomb right between the two, the single-calibration bomb, and the flare bomb. So the RAF plane would go over in mid-afternoon, release one or sometimes two calibration bombs, and within a few hours a broadcast from Germany come on and say: Those heathen Brits, and the Americans, they've just bombed a hospital or a cathedral. We'd get this feedback and say, "Okay, we're 200 yards long," and we'd crank up the knobs. So on the night raid, which would be in the same area, we'd take [into consideration] the system errors. It was extremely interesting to see how that all operated. I was impressed no end about the ingenuity.

Bryant:

The British?

Weiss:

The British. The Mosquitoes were also used to parachute spies and other agents overseas. These were precision drops in bad weather. They'd have to put them in a field [of dimensions] a mile by a mile so that the people who were picking them up could meet them in the middle of the night. We would be at the RAF bases when they were organizing this, and you would see a Lancaster or other aircraft get loaded up with women, young boys, older men and special equipment. In the middle of one of these major raids where there may be, say, 2,000 airplanes, there would be this one other aircraft who snuck in with the force. He would then take off and do his special mission and then join up with the returning bombers on the way home. He was Pathfinder-led.

Bryant:

That was part of getting specific people to specific places?

Weiss:

Right. There was a whole group of people. Some of them were carrying radio beacons; some of them were carrying agents of one sort or another. It wasn't my domain; I didn't get into much of it. But I could see it all going on because we had to check out the equipment in the airplane only hours before they loaded it up to go. I had an experience, which was for me interesting. When the first six Oboe equipments were put together at Radiation Lab and checked out, we did a little bit of pre-flight check-out at Bedford Airport, but we couldn't do a complete systems check. We could do some ranging measurement. The Oboe equipment was packed in big shipping cartons in the radar. They were going to fly a special aircraft out of Washington to bring this gear to England.

Bryant:

Transport it?

Civilian Equivalency Rank

Weiss:

Yes. Oh, an interesting digression. The civilians in the war zone needed military credentials because you get a vehicle, or access to an airfield or BOQ, with military orders. So they had to cut orders for everybody in the war zone. They were just exactly like military orders, but they had a rank there, which was called "civilian equivalency rank," which was what got you the right kind of BOQ. They gave me the "equivalent rank" of a full colonel. Here I was at the age of 23 or 24, way over my head in terms of what I was asked to do and the responsibility I had. But it just got elevated right into this enormous operation, which was gathering momentum.

Bryant:

It made you a senior officer.

Weiss:

I was made a senior officer, and I could go into the BOQ. As you go in, there's usually a guard outside, and he would sort of get ready to stop you: here comes a civilian. He'd look at your papers, and he'd snap to attention and salute. Very out of place. So there was a little bit of that.

Oboe Cont'd.

Weiss:

I was asked to keep those boxes of Oboe equipment in sight unless they were in the hands of a military escort. The Laboratory got me to South Station with Laboratory trucks. It was turned over to an agent in the railroad baggage car, who sat with it here all night, and I was in the adjacent sleeper. We got to Washington, and there were supposed to be some people to meet us. Nobody was there, and I was told not to leave this equipment out of my sight. So I made some frantic phone calls. In a little while a group of Army people showed up with a truck and some armed guards, and they took the boxes. The airplane was delayed a half a day or a day, so they put me up into a hotel in Washington, and they brought the boxes into my bedroom. They showed up in the lobby of the hotel with a whole entourage of military people and me, and they said, "You've got to park these people here for the night." They told me to sleep on the boxes. It was that kind of deal. So in the morning they arrived. They got into the airport, and we flew on the plane. A similar thing happened getting from Liverpool to London. We had armed guards. They weren't on time, and it made me very, very nervous. We eventually got the gear there, uneventfully. But, again, it was kind of an interesting episode. When I read about Bowen's bringing the magnetron to the US and his problems, it was somewhat similar.

Bryant:

Was this Oboe Mark II? Did that distinguish it being a microwave unit?

Weiss:

Yes. I believe that's correct. The original was Oboe, and this was Oboe Mark II. It was ultimately used by the Ninth Air Force trying to bomb the submarine pens and to try to find the remnants of the roving tank groups, I forget what they call them. They were watching the German tanks at night through their intelligence sources. In the middle of the night the Ninth Air Force was asked to go and precision bomb this particular field. The tanks were all under trees and well camouflaged. There was a lot of frantic activity. It turned out there was much too much work for me to possibly keep ahead of the flow. After being there just a year, whoever was in charge of London office decided they'd better send me home because I had lost about 35 pounds, and I was obviously ready to go home. So I left for the U.S. a week or so before the invasion I came back to the Laboratory, got into the systems group, and it wasn't very long before I ended up on Project Cadillac, working again on receivers and system problems.

Project Cadillac

Bryant:

Tell us what Project Cadillac was.

Weiss:

Project Cadillac was a airborne radar and was the predecessor to the AEW. It's a powerful airborne early-warning radar and airborne control station. It went in an airplane with a big radome. There was a version of AEW installed in Navy bomber aircraft. It could land on an aircraft carrier. The first of these Navy systems was in a Grumman TBM, which they called a "pregnant guppy."

Bryant:

Were the radomes underneath?

Weiss:

Underneath, and they filled all the space between. I remember that first conference at Grumman when we described the radar we wanted to install on the airplane. About five or six of us went down to Grumman, and the Grumman engineers were assembled. We had some Navy brass with us. We had the profile of the airplane out, and we said, "what's the biggest thing you can fit between the wheels?" Grumman was thinking about a 3-foot, 2-foot bubble. But we looked at the profile and saw a separation between the wheels when they were down of about 15 feet. When the oleo struts were as low as they go, there was about 2 inches of clearance above the ground. So we filled that whole space up with the radar antennas.

Bryant:

How high could it be?

Weiss:

It was probably 4 feet by 12 feet.

Bryant:

This was a big undercarriage.

Weiss:

Grumman said that this was terrible! It would cut the high top speed down by 25 percent. We said, That's good. We weren't going anywhere with this airplane. We were going to go up and ride over a carrier, and the object was to look at the low flying kamikazes and try to catch them at 120 miles or 140 miles, rather than have them show up on the doorsteps of the ships.

Bryant:

What was the wavelength of this?

Weiss:

It was 10 centimeters, I think.

Bryant:

It's the forerunner of today's AEW?

Weiss:

AEW. Exactly. It's the same thing. The AEW is much more capable as a radar, but the concept was the same.

Bryant:

Did it have the control room in the airplane?

Weiss:

It had a position for about three or four operators topside. There was an enormous amount of equipment. In the TBM, there was only two or three crew in the back, and a pilot and navigator. So there were about five people in that airplane. It was crammed full of electronics and fuel. We had to carry oxygen bottles so we probably got up to 14,000 feet. We stationed in front of the major fleet task group, maybe 50 miles out. It became apparent that there was too much information coming out of the system to be absorbed by any few people up in the airplane. Later, there was a 400 MHz relay from the airplane to the carrier so that the combat information center on the carrier had the same displays as we had. I ended up working on that relay. I think we got RCA to do it, but I was responsible for the systems planning.

Bryant:

This is remoting the video?

Weiss:

Remoting the video.

Bryant:

The video as well as the antenna-pointing information?

Weiss:

The video modulated the rotation signals. So it was really just a remote display of what was coming out of the airborne equipment. That was Project Cadillac. The name came from the test site in Maine on Mount Cadillac, where they put in the ground R&D hardware. There were problems trying to get high-powered transmitters or RF gear not to arc. All the usual problems with half-invented equipment, trying to get reliability.

Bryant:

Did you use a transmitter from some other radar?

Weiss:

It was provided by the transmitter group in the Lab, and it must have been a derivative of an MEW. It wasn't that beefy, but it wasn't very far from it. It was all they could get out of it. I forget the parameters.

Bryant:

And probably a receiver taken from some other system?

Weiss:

That's one very significant element of the Laboratory. Everybody was on the same team, and you learned that if you needed an antenna feed or a piece of RF plumbing, the way to get it was to go down the corridor or down to the next building, sit down with the people, and define what you were looking for, and they were completely supportive. The only problems in getting it done quickly was the competition with all the other laboratory projects.

Cooperative Atmosphere

Bryant:

Did you have to give them a receipt for it so they got credit?

Weiss:

No. There was none of that as I recall. It was very open, very cooperative. You'd call people up. We had many occasions when we'd call the machine shop or go down to the machine shop with something, a choke joint for instance. You'd walk into the machine shop at four-thirty or five on a Friday afternoon, and say, "This is holding up our test work. We need it tomorrow." The guys would work all night. That wasn't considered exceptional. If you needed it, and your project was a priority project, you got all the support you needed. Perhaps one of the things that has served me best in the subsequent years was the recognition that the way to get things done is to find out who has the know-how, anywhere — in the laboratory, in MIT, in industry — and knock on their door and talk to them about it. It's a synergistic way of doing things. There were some people who never learned that lesson, but I grew up in that environment, so I carried it with me. It made it very easy to accomplish projects and programs because the name of the game was to get the answer, not how you did it. That was a lesson that I got out of Radiation Lab, the feeling that good people who were proud or excited about the things they were working on leaned over backwards to get that stuff into your system. It was a very helpful capability and exercise for me.

The thing I haven't seen discussed is the spirit, the esprit de corps. It wasn't just that everybody knew that the whole thing was going to be over in the next year or two. There wasn't any major empire building. People were helpful and cooperative, and there was no parochialism. There must have been a lot, but I didn't see it. I just found that it was just a dynamic, wonderful, exciting place to be because things could happen very rapidly.

Bryant:

You've answered one question here — but I'll just repeat it — in which you summarize some things. To what extent did the flow of information follow the channels defined by the formal organization?

Weiss:

Very rarely. But I didn't see too much of the front office.

Bryant:

Not too much of the front office?

Weiss:

I didn't have any reason to work with them. I worked with people one or two tiers down: some of the group leaders and people in the various laboratories. The only problem you had was priorities. But there was never any problem of cost. You just did it. That was another lesson I learned. I could get on the phone and call somebody at Bell Labs or RCA and say, "I think you guys have worked on a new transmitter tube, and I need some of those real badly. Can you get them for us?" It wasn't a question of figuring out how to write a contract or getting approval to buy tubes. Even if they cost a hundred thousand bucks apiece. I knew I had the support of the people I was with, but I was given an awful lot of freedom to go do whatever I needed to do. If I decided I'd better visit some company out-of-town tomorrow morning, I would just arrange for airplane tickets through a local secretary and do it.

Bryant:

Go down to an RCA plant?

Weiss:

Wherever it was at the time. I'd work out a negotiation with them, just technical man to technical man, and I'd come back, tell the people at the Laboratory, and write a memo of what I did.

Bryant:

You had a Purchasing Department?

Weiss:

Yes. They wanted to be kept informed. As the Lab got older I suspect, we had a purchasing representative come down if there was a major deal. But by in large the paperwork followed the activity. The activity drove what you did tomorrow; you didn't wait to get approval.

Seminars and Information Exchange

Weiss:

In one way this helped: there was a seminar every week in the Laboratory in which somebody was delegated to give a report on what they were doing. Sometimes it was technical work, sometimes people back from a field project. The whole Laboratory technical staff was invited. These were Monday night meetings.

Bryant:

The staff was expected to attend?

Weiss:

Yes. You looked forward to it.

Bryant:

This affected the relations between the technical people and the technicians.

Weiss:

That's correct.

Bryant:

Were technicians not invited?

Weiss:

Normally no, because of space limitation. If your project was up for discussion, you usually asked them to come. Nobody at the door said, you go in, you don't go in. The badge was the way you got recognized by the guard at the door. Typically the technicians or secretaries did not attend these unless their own group was giving a presentation, and then you'd get everybody. In that manner you understood what was going on throughout the whole Lab. You had a feel for it even though you had no particular interface with those people. You very quickly recognized who were the really good people, who were the producers. Even though the Laboratory was full of really topnotch, first-rate people, if you needed an indicator, you'd go and see Willy Higinbotham. I picked that name. But someone who was technically on top of that program, and you'd negotiate with him to get what you wanted.

Bryant:

They were also consultants if you needed answers to problems?

Weiss:

Right. And I had plenty of people flocking to my workbench.

Bryant:

You had freedom to go to somebody?

Weiss:

It was an open door. Something you don't find today, in industry or other laboratories, partly because of security, partly because of financial constraints. And maybe a parochial view about "we do it this way, and what they do is not our problem." But the Laboratory was so productive because everybody got clued in periodically. It was good. The divisions had meetings too. They were usually daytime meetings or late afternoon meetings. By-in-large, the division people all attended, but if you were aware that they were doing some work on magnetron misfiring or something and you were a systems man and had a problem, you'd know where to go. The meetings were posted, and you knew where to attend to get the latest word.

Bryant:

Was there a committee designated to get speakers to talk at these meetings?

Weiss:

Yes, there was.

Bryant:

What was it called?

Weiss:

I don't know. I think the division heads did that. Maybe it was a steering committee function, but I think it was more a planning committee.

Bryant:

There was a steering committee and there was a larger coordinating committee.

Weiss:

Right. It may even have been a subgroup of the steering committee that planned these. I don't know.

Bryant:

One more thing on these meetings. I've heard a great deal from people about the W.W. Hansen Lectures.

Weiss:

Right.

Bryant:

Were they separate, or were they scheduled in with these regular slots?

Weiss:

No, I think that was a separate series. W.W. Hansen was primarily based on the West Coast.

Bryant:

He was working on Long Island.

Weiss:

He was at Sperry, I guess. I think what was set up was this series of lectures.

Bryant:

Did you attend some of these?

Weiss:

Oh, yes. One of the problems I had is that I was an equipment guy. I was a gadgeteer. I was happiest and most productive when I was making something. A lot of these meetings were at a pretty high theoretical level. If Schwinger was talking, I didn't bother going. It was all higher maths, and it was nothing I could understand or even participate in. But things relating to systems or of techniques, technology level, I went to every one. I don't think they kept attendance. The seminars were posted, and you went whenever something looked like you wanted to go.

Bryant:

Now those regular seminars were evening seminars, I gather. After dinner?

Weiss:

Right. After dinner. Either Monday or Tuesday.

Bryant:

And the Hansen Lectures were in the daytime?

Weiss:

I believe they were three to five o'clock or three to six o'clock in the afternoon. I attended some.

Decision Making and Scheduling

Bryant:

Back on the organization, did you have the feeling you had sufficient input on decision-making?

Weiss:

Very much so. It was very fortunate because Lew Turner and Van Voorhis were the people closest to me.

Bryant:

They headed up the receiver group.

Weiss:

Yes. I don't think in the course of all the years I worked with them that they ever did anything but support me. I don't think I had any battles with them. I'd come in with a problem and say, "I think we should put together a couple of special receivers and check them out here and here under these conditions." And they'd say, "Gee, how soon can you do it?" It was always that kind of thing. I didn't realize at the time how unusual that was. I hadn't any other experience. Here I came out of school and the Instrument-Landing Program and then found myself right smack in the middle of Radiation Lab. I never knew that it could be otherwise. I now know.

Bryant:

What internal conflicts were you aware of?

Weiss:

There was always a bind about space. You never had quite enough elbowroom to stretch things out. You'd set up a big new workbench, and before you'd know it there were two people working on the bench instead of one. So space was a problem. Getting things from a cable shop support group. You wanted them yesterday, and they'd put you on the back of the list for the week after yesterday, and it was pacing your project. So if there were battles, it was having to do with getting things accomplished rapidly.

Bryant:

So you didn't have a formal scheduling system?

Weiss:

I think the guy in charge of the systems program put together his idea of a master plan. We'd spend the first three months putting together a breadboard, and we move it to here, and then we do this, and then we do that, and the modulator would come along at this time, and the receiver.

Bryant:

Did you have any feel for how well systematized that was? Was there a form?

Weiss:

No. It was very much an ad-lib thing. It was monitored by technical people.

Bryant:

You started answering the question about the formal scheduling?

Weiss:

I think that if the people in the Laboratory were more experienced and had a good idea of what the problems were going to be, we would have set our sights lower and we probably couldn't have accomplished near as much. We had rather grand plans and were saying, "We've got to do it tomorrow. We've got to get this thing going in three months." A lot of these targets were extraordinarily optimistic in any kind of real world. Targets weren't just made arbitrarily. The group that was working on the thing helped put the thing together, and then everybody pushed hard to make it. Sometimes you made schedules and sometimes you had setbacks. But they were done at the working level. I guess that's the way to put it. The technical people decided how quickly they could do things. The Laboratory was a beehive of activity on Saturdays and Sundays.

Bryant:

You worked officially until noon on Saturday?

Weiss:

I don't think so, but I don't remember. Possibly officially, yes.

Bryant:

And you officially had Sunday off?

Weiss:

I suspect so. You could go in the Laboratory at two a.m. on a Sunday morning, and up and down the corridor there were people working. I wasn't married at the time, so I probably slept in the Lab off and on because it was where I was focused.

Engineers' Relationship to Physicists

Bryant:

We hear that the Lab was an ideal ground for physicists to work. Was there any sharp distinction between physicist and engineer?

Weiss:

Not in the sense of a hierarchy. I think there was a certain amount of natural gravitating. You worked on the things, which you felt were within your scope, within your realm. You weren't excluded from meetings. But you didn't attend a lot of the theoretical work. It just didn't couple to what you were doing. I think it was a very egalitarian kind of place. Everybody did his own thing as best he could. Technicians were invited to parties and so forth. It's a little hard to figure out how you'd do it today. Somehow or another the system's gotten much more structured, and it wouldn't be comfortable to do it today. During the war, there really was no precedent for a lot of these things. People did what seemed natural. Today I don't think you'd do that. There are all kinds of artificial reasons why it wouldn't be good to.

Social Life

Bryant:

Was there a really extensive social life involving lots of members?

Weiss:

Yes. I can remember a whole series of parties. Art Roberts. You've probably heard of his ability to make up songs and parodies about Laboratory work.

Bryant:

Someone was wondering the other day if any records still exist.

Weiss:

There must be some.

Bryant:

Recording somewhere.

Weiss:

Willy Higinbotham, I bet, would know about that. He was one of the vigorous, boisterous guys in the group. He probably would be a good source.

Bryant:

Willy Higinbotham and Art Roberts would be two of the right people?

Weiss:

Yes. And they would lead you to the people who would know. In fact, one of the early Radiation Laboratory bulletins had whole pages of songs that originated inside the Laboratory. Set to some simple tune like The Mikado, which everybody could sing. They were really wonderful. They were kind of unique.

Rad Lab Compared to Los Alamos

Bryant:

You worked at Los Alamos afterwards. You probably have some viewpoint on this. Can you compare the work styles of Los Alamos and Rad Lab?

Weiss:

Let me give you a little preamble. The war was over.

Bryant:

When you went to Los Alamos?

Weiss:

I was out in the USS "Ranger," CV-4. Sailing out of North Island, near San Diego. We were training pilots for the Navy version of the airborne early warning system. We were trying to get AEW aircraft and people set to go and spearhead the invasion of Japan.

Bryant:

That would have been the spring of '45 then?

Weiss:

The spring of '45. Then the bomb was dropped, and the war was over shortly thereafter. Our ship came back to port in the US instead of continuing on to Japan. Back in the Laboratory a few weeks later, I was doing whatever I was doing and Jerrold Zacharias came around and said, "Herbie, you've got to go." And I said, "Go where?" He says, "Los Alamos." It was just a name. Zach (Zacharias) had picked about six of us — Jerry Wiesner, Al Jerrems, Herb Hall and a couple others. The first two atomic bombs, one on Hiroshima and then Nagasaki, were literally put together in the laboratory with bailing wire and string. There are actually photographs of the second bomb as it was pushed out of the airplane. As it started going down, one of the tail fins broke off, the dynamics were so poor. The mechanical engineering was never done except in a quick and dirty way. People were scared to death that the excess vibration would keep the timing circuits from firing. Somebody got the bright idea that these people at Radiation Lab had learned how to package electronics and make airborne gear that would fly reliably. So Zacharias dragged this group out to Los Alamos, presumably for a short period like a year, to look over what they were doing and set up a test program to get their electronics straightened out.

Bryant:

For the future?

Weiss:

For the future. I was one of those people that went. A lot of those guys had other obligations, like Jerry Wiesner, and peeled off after a year. I stayed at Los Alamos for three years. The last year I was very busy on the Bikini bomb test.

Bryant:

So your employment changed?

Weiss:

Yes. When we went out there we became University of California employees. I ended up in the Physics Division doing instrumentation R&D for some of the advanced testing. I was in charge of a ship that carried the timing equipment and the rest of the stuff for the Bikini experiment. I spent three very busy, very wonderful years out in Los Alamos. I came east and met my future wife, and she was gung ho to go to Los Alamos. But again, Jerrold Zacharias said, "Herbie, that's not going to get you anywhere. I don't think you should go there. You've had your three years. That's great." He got me in touch with Raytheon. They needed someone to run their new computer work. I joined that group and spent three years there.

Bryant:

'Forty-eight to when?

Project Charles

Weiss:

'Fifty-one. Then Project Charles got started, which was the concern about the defense of the North American continent. The Soviets had demonstrated they had a hydrogen bomb somewhere in the late 'fifties. It scared the people who were thinking about the defense of the North American continent. They recognized that old-fashioned transport aircraft could fly over the Polar route and drop a bomb on New York. The first we'd hear of it is after the bomb went off. There was no air defense network. None of that was organized. Back in '51, there was the first semblance of the computers — the Whirlwind Computer at MIT and two or three other related projects. The technology was developing to make it feasible to put together a network of radars feeding data into a computer so that you could have in one place a map of the air activity over a large geographical area. Because with the speed of action, there was no way in which you could get enough warning to get a fighter plane up an intercept an intruding aircraft and still be in the zone of the same radar sensor.

Bryant:

Are you talking about Project Charles?

Weiss:

Project Charles was the study group that ended up deciding that there ought to be an air defense.

Bryant:

Did that lead to Lincoln Labs?

Weiss:

Yes. After the study group, they recommended that they needed warning networks in the north. You needed the SAGE system (or what became known as the SAGE), an integrated, computer-based, data information handling system. Then the way these things go, the study group recommended that there be a focused effort like Radiation Laboratory to make that go. Some of the same principals were there: Al Hill, Jerrold Zacharias, and George Valley.

Bryant:

Did Wheeler Loomis have any function in Project Charles?

Weiss:

I'm sure he was in some of the meetings, but. I remember Zach as being the kingpin of that.

Bryant:

So there was a pattern for setting that up. It would have been influenced by Rad Lab.

Weiss:

Exactly! 100 percent! The Secretary of the Air Force, I guess, asked MIT to reconstitute Radiation Lab, and it was impossible since everyone had dispersed.

Bryant:

Wasn't it Project Charles?

DEW Line Radars

Weiss:

The meetings were held on the Charles River in the upper floor of what was then the Lever Brothers Building, right on the river. The top floor was a secure area. There was a whole series of meetings. There was pretty strong representation from Bell Labs, some very good people. Henry Bode and some of the others were there. A few people from industry. A few people from universities all over. Probably a group of maybe 20, 25 people deliberated for maybe five or six months. They came up with the basic concept of an early warning network and a DEW line. Communications from the DEW line relayed back to Colorado Springs. So when Al Hill, who became, I believe, the first director (I think he was the first director) of Lincoln Lab, I got a phone call at Raytheon, and he asked me to come over for lunch. That afternoon I told Raytheon "goodbye." I was going to go and join the new laboratory. I ended up being in charge of putting together a team of people to put together the early warning radars for the DEW line.

Bryant:

That was 1951?

Weiss:

'Fifty-one. It probably took two to three years to get the radars through the R&D cycle. The big problem was that you had to have a very minimal crew in the field. The radars were relatively short-range, line-of-sight detection systems. If you had long-range radars situated far apart, the Soviets could fly low. They could go below the coverage. Because it took so long to get the system manned and organized and planned, you knew the Soviets would have a detailed road map of what you had there, and they could under fly it if they wanted to. That meant the stations had to be pretty close together, we also ended up with some CW Doppler gap-filler radar with fixed antennas.

Bryant:

What radars did you use?

Weiss:

We had to invent it. [In order to] detect aircraft in heavy ground clutter we had to get a pulse Doppler radar to work, and the only one available at that time still were magnetrons. We had to build an MTI system based on a local oscillator that was phase-locked every pulse. And Doppler filters. The filters were built by the same technique. We called up Bell Labs and said, "We need a bunch of filters for 30 radar sites. And they have to have very steep skirts." We gave them the characteristics, and it wasn't very long before they put a whole team to work. In five or six months we had the jazziest filters you can imagine.

Bryant:

So you really had a coherent Doppler system, even without a coherent radio transmitter?

Weiss:

Yes. It never worked the way it should. It probably had a sub clutter detectability of some 30 dB, which was pretty good. But there were still places in the radar coverage where you just couldn't get the capability you wanted. Fortunately, a good part of the Arctic is relatively flat. Particularly if you're on the northern coast looking seaward.

Bryant:

What level of frequency was it?

Weiss:

That was L-band. It was a pulsed L. We started with the TPS-1D, which was an Army "L" band field transportable radar. We used that as the bare bones to start our experiments. It was a radar that was in production. We put in a couple of test system up in the Arctic — Point Barrow for one and somewhere else for another. We did some experiments for six months up there. There was always jury-rigging and fixing up the gear. Because, again, the only real problem was the MTI, maintaining sub-weather visibility with magnetrons being sensitive to long line and voltage valuations effects. We just didn't have a coherent radar.

Bryant:

RF amplifiers?

Weiss:

That came along later. We got the 35 DEW line radars in using a radar that Raytheon built to our specs. They were awarded a production contract and built a ground-based version of the TPS-1D with a much better antenna and the Doppler filters. We did all the bread boarding at Lincoln and on the roof and in field sites. Then we developed a CW Doppler radar called Flutter. It's written up in the IEEE.

Bryant:

Was it a monostatic radar?

Weiss:

It was a bistatic with fixed beams. Again, a sophisticated Doppler processor. The whole objective was to fill the gaps with simple equipment. We used pulse compression technique to achieve small range resolution. That led later to a radar that was specifically designed for that purpose. It was a 600 MHz radar. It had a pulsed, amplifier klystron final, and it was APS 59. I may have the number wrong; I think that was it. It had a big dish inside a radom. We put, I'd say, five of those across Greenland. I say "we." The heavy engineering, the systems field work, the logistics (which was really the only part that makes the Arctic worse than operating in Boston), the roads, and the transportation. That project logistics support was handed to Bell Labs, to Western Electric really. They did the heavy work and spent the big money, and we were responsible for the design of the electronics. Another part of the Laboratory worked on the scatter communication. We had some big fixed dishes that forward scattered about 400 miles from the Arctic to collection points further down. That's quite a digression from Radiation Lab, but it's an exact derivative.

Bryant:

We're interested in what evolved, what the fallout was, and it appears to have been considerable.

Weiss:

The organization and basic philosophy of operations was patterned after Radiation Lab. There weren't too many Radiation Lab people at Lincoln; but the first director was a Rad Lab alumni. Of the many hundreds of people at Lincoln, there couldn't have been but 20 Rad Lab people.

Bryant:

You speak of the 1950-51 time there. Of course this reminds you of the Korean Conflict. Did Radiation Lab radar research surface there?

Weiss:

Very much so.

Bryant:

Which ones did?

Weiss:

We worked on some esoteric things like mine-detecting radars, very low frequency systems. Looking for changes in the dielectric constant of the earth.

Bryant:

This would have been on behalf of helping things in Korea?

Weiss:

Korea, and also in Vietnam later on. Then we developed some radar that were very small field-transportable radars which would see moving objects (people) through foliage. These were low frequency, as I recall, 400 MHz. They were almost backpack sets, but they were coherent all the way and had very good Doppler processing. You could see a walking man at a range of one mile in the bushes.

MTI

Bryant:

You spoke of MTI. That was actually a development in the Radiation Lab?

Weiss:

In the early Radiation, [Lab work] and then it got further refined as systems technology got better. It was a technique very heavily at the root of the DEW line and the ballistic missile warning system (BMWS).

Bryant:

Which of the Radiation Laboratory radar did it find its way into, or did it?

Weiss:

In the Radiation Lab, I'm sure there was an MTI in the 584 and in the AEW. We had a problem of trying to cancel clutter.

Bryant:

Just to get rid of clutter?

Weiss:

It was probably a very poor 2-pulse delay line system.

Bryant:

Was that a delay line in the IF?

Weiss:

I think so. It was a 2-pulse canceller, but you could wipe out the heavy stuff. With AEW you could get reasonable performance because you were working over the ocean, and the density and frequency distribution of clutter made it possible to detect a high-speed, moving aircraft. That's really what saved you. The fact that the targets of interest were moving at hundreds of miles an hour.

Rad Lab Interaciton with Private Industry

Bryant:

Did you have any particular observation about the interaction with industry?

Weiss:

During Radiation Lab days?

Bryant:

Yes.

Weiss:

Yes. I was building receivers, such as IF strips and things like this, and they were needed in production quantities. For instance, the receiver in the AIA radar was one of mine developments. The airborne interceptor. Sperry got into the radar business by getting a contract to work on the AIA. They built a big plant in Garden City. But I remember going down there with a model of the IF strip and handmade circuit diagram I came up with, and sat down with their people and said, "This is what you should copy. You've just got to figure out how to make hundreds of those." They did a repackaging job, and I was down there to review the progress until they got the system going. The same with Raytheon. I carried the SG radar IF strip again, only that part of the system, to Raytheon, and they were, for all practical purposes at that time (at least I looked upon them), a company that made battery chargers. The electronics industry in 1943 was pretty minimal. Route 128 did not exist.

Bryant:

It was still pretty small at that time. Yes.

Weiss:

Out of this activity, the whole industry grew up. The enormous amount of effort and the requirement to get a lot of stuff in a hurry took all of these companies and pushed them at an enormous rate.

Bryant:

This was a receiver group.

Weiss:

That's right.

Bryant:

But the receiver also included a mixer, the RF.

Weiss:

Yes. The mixers and that stuff came out of the people in the RF components group. They did development tests. Usually when you're planning a new system or new requirement, you sit around a table and talk about each element and the overall packaging.

Bryant:

Whose responsibility was it to coordinate these?

Weiss:

There was a project leader or program leader. It was his job to put together the system block diagram and to pick and choose what went into the system. I don't know how many radars all told, maybe 75 different ones that came out of the Lab before the war was over.

Bryant:

I heard a number of 100.

Weiss:

I don't know. Could be. Each one had some one person who was nominally in charge. There was a whole family. There was like an SG-1, SG-2, SG-3, and SG-4. These were frequently the same thing with a new kind of front end or a different antenna feed or a different something. There were many radars which were just derivatives of a common one: Shipboard radar, airborne radar, and something else.

Portable Receiver

Bryant:

What do you consider your most important contribution at Radiation Lab?

Weiss:

I was very lucky in a sense. I had a good enough feel for radio electronics in general. When I got into the receiver business there were people who were working to get a stable, 50 or 60 dB amplifier with a 2-4 MHz band with operating at a center frequency of 20 or 30 MHz. It was almost impossible. Energy was leaking out of the power leads and the by electro cycle coupling to keep them stable. People were buttoning them up in tin boxes. Every stage had its own practically waterproof little cell, and it got to be a mechanical kludge, and very, difficult and expensive. After working away at the problem for a couple of years, I remember Jim Lawson having a receiver you could hardly lift; it was on a big brass board. From stage 1 to stage 2, and you go through the copper barrier, and the RF chokes and everything. I ended up evolving a receiver design that was only 1 1/2" wide and 8 inches long. All the components were very low against the bottom plate and only about 1 inch high. I ended up with a receiver strip that met all the requirements. At one time it was called the Weiss receiver, but I guess it got so universal that everybody used it. It was everybody's receiver. It saw service in 80 percent of the radar equipment that was ever delivered by the Lab and industry. Sooner or later everybody did a little embroidering on it, but it was the same basic thing. The receiver went from weighing 50 pounds to weighing 50 ounces.

Bryant:

You really evolved some products, I'd say. Some products that we could use on other things.

Weiss:

Yes. We also had a very difficult problem keeping the LO tuned to tracking the magnetron. In using the IF, the discriminator circuit, to decide whether the pulses were high or low, we could get a DC feedback control to control the local oscillator frequency.

Bryant:

The discriminator is a microwave bridge?

Weiss:

It was all receiver technology. It was low-power gadgetry. Those are the things I can identify as having specifically worked on that got used literally all over the place.

Instrument Landing Project

Bryant:

I think that's extremely interesting coverage on the Radiation Lab. It gives us some different viewpoints and gives us some more leads. I'd like, if we could, to go back to some to your time as a student at MIT in the Instrument Landing Project. I'm particularly interested in getting better documentation of that and also something on Loomis Labs. Frank Lewis and Bill Tuller and someone else from your group went for the summer down at Loomis Labs. In Tuxedo Park, N.Y. That was the summer of 1940?

Weiss:

That sounds right.

Bryant:

They were down there when the Tizard Mission came in, for example, and you were still active at MIT on the same project.

Weiss:

Right. I came back and forth. I visited Tuxedo a few weekends in those days, but I wasn't working there in a concentrated way.

Bryant:

Were you there on a social visit?

Weiss:

No. There were some parts we working on that were similar. As I recall, they were pushing more general microwave technology (I may have it wrong). We were focused on an instrument-landing system. The microwave landing system used horn antennas that were developed by Professor Barrow.

Bryant:

He and his students?

Weiss:

He and his students. I was one of his students, too. The horns were built using plywood panels, with copper foil the horns were quite long perhaps 12 feet. Four horns — right, left, up, down were used. We had a switching transmitter which was a klystron that the Varian brothers brought to the east coast with a vacuum pump on it. This was a tube about 600 MHz.

Bryant:

I think it was 40 centimeter. So that would be a pretty big horn. If you want a 40 dB gain in a horn, it's got to be pretty long.

Weiss:

The switching was done by a cam-operated motor-driven switch working with 1/4 wave coaxial lines. Tone modulation was generated by a rotating gear and earphones mounted near them. The tone was synchronized to the switching. You got the high-low tone where it was high on one horn and low on the other.

Bryant:

It made a glide path.

Weiss:

It made a glide path and another set for the localizer, where the horns were a little different geometry. The test aircraft was a Boeing 247 (similar to a DC3) that was assigned to the blind-landing project. It was based at Wright Field. We equipped the aircraft with receivers and indicators and the pilot had a cross-pointer meter. During test flights the plane would move over to the get oriented, and then the pilot had a correct approval area about 5 miles from the runway screen pulled down in front his windshield. He flew the plane by watching the cross-pointer needles. We started making flights into Logan early in the morning because the first transport from Newark, a Ford-Tri motor came in about eight or eight-thirty in the morning. So from first light, five o'clock, until eight we had access to the runway. We only instrumented one runway, and it was used independently of the direction the wind blew. There probably were only two runways at Logan at that time.

Bryant:

So what time period were these tests?

Weiss:

'Thirty-nine, 'forty? In that time frame. Among the other jobs I had to do was to take the batteries out of the plane every night, take them into the hangar, and charge them up. Bring them up in the morning every day and put them in the airplane.

Bryant:

I have it on record that that klystron, which was a continuously pumped one, came with its own vacuum pumps.

Weiss:

Right.

Bryant:

It was actually built by Sperry. Sperry in San Carlos. The man that came with it was Joseph Caldwell.

Weiss:

It's a familiar name.

Bryant:

You remember him?

Weiss:

Yes. I do.

Bryant:

He was a student at MIT and just getting a master's.

Weiss:

On the other hand, I thought the early ones came out of Stanford or wherever the Varian brothers were hanging their hat.

Bryant:

No. It was a prototype from Stanford, but I'm pretty sure that any that got in the field were actually made in the Sperry plant just up the road in San Carlos.

Weiss:

Okay. Could have been. I didn't see them until they arrived on site. I remember I met Ralph Metcalf.

Bryant:

Who?

Weiss:

Metcalf, who was the Air Force liaison man.

Bryant:

Yes. Where was he?

Weiss:

Wright Field.

Bryant:

No, he was FAA. He was in Washington.

Weiss:

CAA.

Bryant:

CAA. Civil Aeronautics started at that point. He's the one that originated this idea of a landing system, the 3-point thing, and the idea that you could you could duplicate it from optics to microwave.

Weiss:

Right.

Bryant:

That was about '36, and it got funded a year later. If I'm not mistaken, it was partially sponsored by Sperry and partly by CAA. I'm not sure.

Weiss:

Could well be. Barrow was very much involved with Sperry.

Bryant:

Yes. But Draper also got involved in the blind-landing project, didn't he? On displays and things?

Weiss:

Not to my knowledge. He might have. The project consisted of probably three or four professors; two or three people more senior than me, and maybe one or two others and two technicians.

Bryant:

Who were your colleagues then?

Weiss:

Frank Lewis, Don Kerr, Bill Tuller.

Bryant:

What was your job title in this?

Weiss:

I was a graduate student technician or something. An assistant.

Bryant:

And Frank Lewis?

Weiss:

He was probably a research associate.

Bryant:

Is that a higher title?

Weiss:

A bit higher, yes. A year or two ahead. But when it came down to making the gear go, there were about three of us that did the bench work.

Bryant:

What about Bill Tuller? Was he the same level?

Weiss:

Yes. I recall having put the receiver together. Frank Lewis and Don Kerr had a heavy hand in the antenna.

Bryant:

Who supervised the group?

Weiss:

I think Frank was my closest associate as supervisor. William Hall and Bowles did the RF end, and Hall probably did the system. I was just one step away from a lab technician.

Bryant:

Frank Lewis has described himself as doing lots of the flight-testing.

Weiss:

Yes. I did a lot of that, too.

Bryant:

So you shared the flight-testing?

Weiss:

Yes, I did a lot of that. I can remember one memorable day. Usually there was a pilot from Wright Field. Frequently we'd show up at the airport, and there were just two of us or three, sometimes four. Somebody went to the ground site and checked it out, turned it on. The pilot and one or two others went in the airplane. Many times I was the only one on the airplane with the pilot. It got to be routine that the pilot would bring the plane in for a landing. Frequently we didn't quite touch down; we'd come up and around and make as many passes as we could in the course of two or three hours, which may have been ten or twelve. I ended up flying the Boeing 247 without a day's worth of instruction.

Bryant:

No instructions?

Weiss:

No instructions. I watched by doing. After being around there for a couple of weeks, it got to be pretty obvious what the pilot did. Usually when the instrument landing was happening the copilot would look out the windscreen and watch for traffic and alert the pilot if something went wrong. He was flying in on meters, and we had analog-type meters, paper tapes, recording the error-signal beam, the course deviations.

Bryant:

You took data?

Weiss:

Yes. Reams and reams of paper tape had to come back and be painfully analyzed. Ultimately, we had a couple of girls that were doing some of that.

Bryant:

So what kind of report did you make on that?

Weiss:

There was a lot of report documentation. Much of that came out of Bill Hall's department. Maybe Frank Lewis and others did some of it. I provided the flight test data and some interpretation, but the actual system reports and the reports to the CAA were pretty much handled by others. There's a good trail of documents if one could ever find them. They're in the MIT library, I would assume.

Bryant:

This project got wound up at the end of '40, first of '41?

Weiss:

Yes. Priorities took over, and all the people got drained off to do wartime work.

Bryant:

What was the end product, the end use?

Weiss:

I think the Wright Field people went to ITT. It wasn't called ITT then; it was called Federal Laboratories, I believe. They wrote the specifications for a prototype system, which then that ended up being built by the ITT people.

Bryant:

Of course it was a lower-frequency system. There must have been fly-offs competing with you.

Weiss:

They were. And the ILS emerged from that with "our" microwave system, which didn't win out in terms of the specifics, but the block diagram and the rest of it propagated into a future system. The technology moved out.

Bryant:

I think that Sperry also built a 10-centimeter version, which also got in the fly-off.

Weiss:

I think that's right.

Bryant:

I think that what we call the ILS now is the one that won out anyway.

Weiss:

Right. That was the one done by Andy Alford and the people at ITT.

Bryant:

It was first designed by a little company down in Washington, DC.

Weiss:

Okay.

Bryant:

Being a contractor, they gave up the drawings, and other people bid. Somebody underbid them.

Weiss:

Okay. I wasn't too tuned in on a lot of that because that wasn't where I was focused. But that's my view of what we were doing. We were trying to make that gear work out at Logan and in the lab.

Bryant:

But nevertheless, the experience that you people got was used.

Weiss:

Yes, we were very concerned about the bumps in the glide path due to the land-water interface and multipath reflections. We parked trucks off one side and looked at the beam bending and recorded that. We had a truck with a very tall mast made from stepladders with a test horn on top. We would run back and forth on the runway and measure signals. Recordings were all on Esterline Augus paper tape.

Bryant:

And you had to eyeball it to pick it off.

Weiss:

Yes, it was very tedious.

Bryant:

Do you recall the truck that they installed the gear in the Loomis Lab that they made down there?

Weiss:

Yes. If I recall, I know there was such a thing.

Bryant:

Working at 10 centimeter, their horns were a little smaller, I guess.

Weiss:

Right. Yes, in fact, that's the break. I think the Loomis Lab focus was on centimeter work, and the work at MIT was at lower frequencies.