The World's First Microprocessor: F-14 Central Air Data Computer

Since a few people have asked how the program counter can be stored in the ROM. It was a special register physically on the ROM chip, not a read-only address in ROM itself. Ray's paper states it was resettable and steppable and could accept an address input. So, I'm 95% sure that allowed for full program flow control. @phirenz makes a good argument for why this may not be quite so simple though....and may have actually required additional ICs to actually implement. The SAAB Viggen is getting a lot of mentions in the comments. It had a highly advanced flight computer composed of many discrete ICs. Not a microprocessor but very impressive nontheless. I am considering doing a video about it in the future. The 'MiG-25' at 6:11 is actually a MiG-31. Thanks @AvArIeNmArKu4 An ‘assembler’ translates to machine code, not a compiler. Thanks @Mat-Ellis Swing wings are a subset of variable wing geometry. Variable wing geometries may be implemented in other configurations and the field is not 'obsolete' as I stated. Thanks @nobodynoone2500 31:48 bottom line: "U if P > L" should be "U if P > U". Thanks @MatthijsvanDuin (I'm really mad I got that one wrong!) 10:00 - Lateral Axis, not longitudinal axis. So, the aircraft is pitch stable. Thanks @UnitSe7en 45:00 - The hardware prototype ran at the same speed as the final product. And yes, I know higher aspect ratio doesn't equal more drag (it's the opposite for subsonic flight). I was trying to simplify and probably simplified a bit too much...I said I always screw up supersonic flight discussions.

The old chip designers were crazy. No simulations, no HDL, no DRC/LVS. They would cut photomasks by hand. Imagine seeing some bug in silicon and coming up with the concept of setup and hold time to explain it.

Having flown the F-14A "Tomcat/Turkey" and then going on after my time in the Navy to work in the computer world... I can't count the number of times I had to bite my lip during conversations about CPUs and sit and wonder "when" until the Osborne, XT, Kaypro and Compaqs came online. We knew the processor was there however we really didn't get into in any depth. We were just dumb Aviators... NFOs. Coming from the A-4 "Skyhawk/Scooter", my initial instincts were to turn it off and control sweep manually. But, I came to trust it and in ACM school learned when to turn it off so as to fool the adversary as to your airspeed, turn it back on to get into position to get a splash. The real beauty of Bob Kress' overall designed was that he used this computer control and the airframe design to do something completely new... it didn't roll at the nose, but at the HUD. So when engaged in ACM, the plane rolled at your eyes, not your feet - Evolutionary. I never met Ray, but I did get to meet Bob in the mid-80s in Bethpage, NY. Was that a Data General Nova in your video (yellow/brown switches)? Worked on those too. I watched this with great interest.

The F-14 was the equivalent of the US Navy's current NGAD (next generation air dominance) program for 6th generation fighters. It was large, expensive, and had computing capabilities that people didn't realize were possible.

Top Gun was popular because it was the first movie where the air to air scenes didn’t look like tacked on scenes filmed in the wrong aspect ratio. Everything flowed together, and it was a good yarn of a story.

"It was in TopGun. You know, the film about volleyball" 😅 So true

I worked on the 4004 back in the day for Intel. It was not a stand alone chip either It required a clock chip and a couple level translators. It was a PMOS chip and did not work with standard logic. The IC's required were the 4001, 4002 and 4024 as I recall.

I'd say the F14 was the most intimidating looking fighter for its era. The F22 with 'symbiote' skin is more mean looking imho.

I entered the USAF in 1978 and was a aircraft mechanic on C5’S they had a top secret (or at minimum secret) system called “ MADAR” (Malfunction - Data - And - Recording) it basically diagnosed the plane in real time and when called up the mechanic on board could figure out what he needed to repair the aircraft it also could be downloaded to put in the aircraft records for future use. Pretty cool stuff for that day!

I grew up around that airplane. It was the topic of conversation for decades because my old man was a test pilot who flew f-4's then moved to f-14s. He retired as the director of flight systems. For his masters he wrote a program that let them load and analyze flight data beyond the memory capacity of the old mainframes. Nasa was building the x-29 at the time and everyone in flight test needed more capabilities to analyze flight data.

I remember it could perform 100k operations per second, which was unbelievable. I believe it could track 9 bogies and shoot at 6 simultaneously. Pretty crazy stuff back then.

Note on the glove vanes. They were designed to preserve agility at high supersonic speeds and would have had little effect at lower speeds. It was later found there was almost never a need for dogfighting at supersonic velocities; combat quickly became subsonic where the glove vanes gave no advantage As a result, glove vanes were disabled and/or deleted from later production runs to save weight and maintenance.

Imagine this is the exact field my undergraduate education was happened to be in, and they failed to give us the proper prospect of what we were actually learning over there breaks my heart, imagine a one hour presentation equal to this could have turned my entire understanding of my field around, and then... it was heartwarming to see even after 20 years of shelving my education i still fully understood all of this... thank you for the effort, both thorough research and admirable presentation... you sir, are a wonderful teacher...

Professor Frank: "I predict that in 100 years, computers will be twice as powerful, 10,000 times larger and so expensive that only the five richest kings of Europe will own them.”

Fascinating! In the early 80s, I worked in Garret Airesearch's environmental test lab. I received my first Confidential clearance so that I could work on the SCADC program. I can't remember the F-14 system ever being mentioned back then, but that could be just due to oldish age. The SCADC was a standardized air data computer that was intended to replace older units on A-6, A-7, and A-4 aircraft . The same electronics components but packaged to fit in the existing electronics bays of older aircraft. There were four total configurations, the fourth being sort of universal fit. Seeing this video, I can see the similarities. Environmental testing was to MIL-STD-510...vibration, temperature, altitude, humidity, etc. Fun time for me working with centrifuge, explosive shock testing, acoustic shock, explosive atmosphere. I left GA shortly after completion of these tests, going on to work at McDonnel Douglas on C-17 (FCSS and Flight Test and Escape Systems (ACES II Advanced Recovery Sequencer, a compact digital computer itself).

I love small YouTubers who put in the effort and research. I know the work it takes when doing it alone. Great video, Alex! You now have another sub.

This content is much appreciated , this officially pushes my level of F-14 geek to that next level that my old ride or die will never surpass . Cheers M8t!!!

What's so interesting to me is how the forefront of so many technologies came together in military applications in the cold war, and not just in the US. In Sweden Ericsson (of later cellphone fame) cut their teeth on the Saab Viggen's onboard computer.

In 1975 I was trying to work on the f-111, as a result I also did work on f-14s that came into the air base their systems are much alike because Grumman was a partner in the building of the f-111. You might be surprised to know that the F4 was originally designated the f-110 . As a result I did work on several f-14s and was familiar with their systems. Because it had to integrate a lot of mechanically driven actuators and control systems, it did require a lot and I do mean a lot of Maintenance time to keep it in the air. We complain today about the F-22 never being deployed with more than five planes at a time, and you are generally lucky if you can keep 50% of the F-22 flying at any given time. Much was the same about the f-14. It was an extremely difficult plane to keep flying. Especially in its first iteration. Iran was extremely short-sighted attempting to use that as their primary fighter. I'm sure that some mechanism of the are data computers were reduced in function for their application. However, I also worked with many Iranians. They were extremely good at understanding Electronics to the highest degree of the day. After having worked on a few of the f-14s I understand exactly why. When Carter cut our nation's throat and increase the instability in the Middle East by forcing the Shah out of Iran. It quickly rendered the vast majority of the Iranian Air Force, notably the f-14s out of existence until they can figure out how to get parts for them. They quickly learned how to build their own parts for those aircraft. That's why they still had several of them flying as of just a few years ago, I don't know if any are flying today. The earliest iteration of the F-14 was nothing to behold except when it was brand spanking new and everything worked on it properly. That was not always the case, as a matter of fact, it was rarely the case. I do not know if your remark about the f11 being difficult to fly while changing its wing sweep is true, it was never true on the f-111f model that I was tasked with. I also never had a problem flying the F-111 simulator, as I was the first one that the simulator Commander had ever seen fly it for the first time and not cause it to crash. I am not certain that we had chipsets in any of our flight data computers. We may have had them in the nav computer because even though it took the old school tape to load Mission parameters. The F model could be tasked with running a alternate routes to and from the bombing point, and never exceed 400 ft off the deck while doing so. You rarely would do a mission and approach a Target in excess of Mach 1 because you would leave a clear Sonic Trail. However you could do so quite easily. I never got into an F-14 simulator during my time in the Air Force because we didn't have any. But as an avionics Tech I was able to show them how to do things like engage terrain following radar while in articulated Terrain. That procedure leads me to the concept that we may have had some sort of microprocessor in the F-111. I cannot be certain, but it is possible. I also have a good feeling that given the restrictions that you had to mechanically put into your movement of the wing at times and other clues, that there was no chip on the flight data system, except in regards to navigation. I did see several iterations of the navigation computer in other devices, some still in the 1970s as a matter of fact. The last iteration of the F-14 was the most capable and had they upgraded it 2 a more powerful set of engines, something closer to what the f11f model, which had the same engines as the early F-16 and f-15, it may have been a much better aircraft. The unique issue with the high bypass turbofan hybrid engines, was that if you pulled back power on it too far and weren't paying close attention, you would scrub off speed at 50 knots per second. That is slowing down at a really fast rate and will you would get yourself in trouble, perhaps that's why you made the claim that the F-111 was hard to fly in transition. I never found such to be the case. You just had to remember to always run with a little bit more throttle than you thought was necessary. It was easy to adjust the speed of the f11 merely by sweeping the wings forward. With five stages of afterburner, you didn't even want to be on stage 1 while actually performing a mission. The f11 I would contend still to this day would be impervious to even the most modern anti-aircraft systems. There just isn't enough time to see it recognize it and shoot at it before it's already past you. Being able to Chase and shoot it down would be a Fool's errand. Especially if you were in any kind of articulated terrain, the ability to actually stay with it would be difficult in the extreme. Aircraft of North Vietnam even found the a model impossible to follow. That was however a much earlier time frame.

Worth noting that when transitioning to supersonic flight, the center of pressure moves back on every aircraft. This is not only due to the F-14's swing wings but the interaction of pressure with supersonic shocks.