F8 Fly-By-Wire System (Apollo Guidance Computer Part 31)

We get a chance to inspect the actual Apollo Guidance System that flew in NASA's F8 Digital Fly-By-Wire experimental plane. We explain how it worked, and recover the software from its core rope memory. The result is a bit of a surprise!
Apollo Guidance Computer Restoration Series: • Apollo Guidance Comput...
More videos showing some of Steve Jurvetson’s collection:
Steve’s collection part 1: • Steve Jurvetson’s Spac...
Steve’s collection part 2: • Steve Jurvetson’s Spac...
Steve’s collection part 3: • Steve Jurvetson’s Spac...
Virtual AGC Github repository:
github.com/virtualagc/virtualagc
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Get more technical info on the companion site: www.curiousmarc.com
Contact info: kzbin.infoa...
00:00 Summary of previous episodes
02:05 The F8 Fly-By-Wire pallet
03:43 Why Digital Fly-By-Wire?
06:24 NASA Dryden Flight Research Center
08:08 NASA's F8 DFBW program
14:10 Shuttle support missions
15:20 Inspecting the pallet
19:05 Apollo SPS engine
20:43 Core rope extraction
24:58 Liquid Nitrogen cooling
25:56 Reading the core ropes
29:22 Running and explaining the recovered software
32:20 Mike's core rope recovery to date

[@Jerry_from_analytics]

In 3 to 5 years: "So here we are at Rocket Garden and this is Saturn V rocket. We're about to try to power it up and see if it works, fix any problems we find and do a launch sequence dry run".

[@gryffuscze]

🤣 I hear it in my head with Marc's voice!

[@cpt_nordbart]

Snoopy is still out there.

[@ReneSchickbauer]

That would be OK. I'm more worried about the future series about "An anonymous collector has lend us a warhead lost in a historic Broken Arrow incident and we going to restore it". Especially given that the guys already know how to control rockets and and supersonic jets. I mean, technically Marc's team has more access to technology capable of delivering a first strike than North Korea ;-)

[@tonkuhn]

By the end of the decade...

[@sarhtaq]

@@gryffuscze Me too, including the elevator music. ;)

[@someoneoutthere7512]

Mike knows more about the AGC software than anyone currently alive I bet.

[@eliotmansfield]

subtle 😂

[@milesallen7339]

Dudes a gangster!

[@PaulLoveless-Cincinnati]

Imagine dumping an incredibly obscure yet Nationally important ROM from the early 70's and immediately running it on emulated hardware. I can not imagine something more cool.

[@malcolmgibson6288]

It's always a good day when Marc gets curious.

[@mbirth]

And when Mike is learning the ropes.

[@tbp-channel8870]

Indeed, about all the de-flopments happened.. I love his dialect.. or slang.. :)

[@Alexander-the-ok]

I almost fell off my chair when I saw the thumbnail for this. I assumed the DFBW pallets had been long since discarded. Absolutely stunning work, Mike deserves nothing but praise for preserving the code from this pivotal piece of computing and aeronautical history.

[@arimunic]

Love your video on this topic. Glad to see you in the comment section!

[@ceedee9186]

I fell from my chair too Alex.

[@sfperalta]

I had the privilege of working as an engineering intern at NASA Dryden (now Armstrong) Flight Research Center during the late 1970s in the Flight Systems Technical Laboratory. I remember sitting in the F-8 Fly-By-Wire cockpit assisting in some pre-flight testing. (Being duly warned about the "live" ejection seat, I made sure to touch nothing!). I don't know if this F-8 had the AGC or the later version of the FBW electronics, but I can certify that the F-8 is a HUGE aircraft. As a young intern it seemed bigger than any fighter aircraft should have been. In my later career I worked briefly as a field service engineer, then for over 35 years as a software engineer (a much easier job... physically, at least). NASA was a dream job that allowed me to work around some of the most amazing aerospace tech of the day. I even got to witness the Space Shuttle Approach and Landing tests from the Dryden flight line. Wow. I am forever grateful for having had that opportunity.

[@OrangeDurito]

This is awesome! Definitely an opportunity of a lifetime. Thank you for sharing your story!

[@KallePihlajasaari]

Great stuf. Please write down here or in a blog anything that you recall from those years that would otherwise be lost to history. The internet never forgets but us humans do. Mention names of people and places, and especially things that were never written down. They discussed the LN2 cooling system, do you remember how it was filled, how often?

[@graemedavidson499]

Flying by wire, controlled by rope and going at a rate of knots… Joking aside, an amazing achievement by all and astonishing to see Mike extract and start executing the code in the emulator on the spot!

[@MichaelOfRohan]

Thats good

[@PixelSchnitzel]

It would be hard to overstate how important Mike is -- and indeed all of Marc's crew -- to capturing and preserving some of the most important technical history of mankind.

[@PeterScream]

oh no I just binged through the whole AGC playlist. : ( - It was an aswesome ride, cant wait for more

[@talesmaschio]

Guys, you are from another world. No pun intended. As an electronics engineer and space fan, it fascinates me to watch your videos and see what both the Apollo program and you could/can achieve. Amazing. Thanks for bringing all this history to light and letting us watch it happen.

[@macupgrader]

I suppose the obvious question given that now we know the team has access to an AGC in the hands of an enthusiastic collector (whom we've already seen enjoys seeing the things in his collection actually function) is: Should we hope to see another AGC restoration series at some point in the future? (With Mr. Jurvetson's kind permission, of course 😁) I can't imagine you guys wouldn't jump at the opportunity to do it again. I think I speak for all of us when I say that we would be incredibly excited to see "Apollo Guidance Computer Restoration II: The Potting Strikes Back" 😅

[@ginabrown3093]

This was my first project as a coop student. Ken Szalai and Dwain Deets were the driving forces and i learned the biz on that airplane. Still remember some of th DSKY codes

[@AdjustableSquelch]

Any technical university with a computing department worth its salt should be handing out honorary doctorates to you guys.

[@OrangeDurito]

I cent percent agree. This is top-tier engineering.

[@benswinter]

Every time I hear "if you follow the channel..." in Marc's voice, I swear my blood pressure drops a few points because I know I'm about to learn something new and interesting.

[@hornorama]

Terrific work. Future tech historians owe you so much!!

[@jpjude68]

the digital fly-by-wire on the F8 was covered by another youtuber called "Alexander the ok", the video is named "Digital Fly-By-Wire: The Apollo Guidance Computer's final gift to the world"

[@Alexander-the-ok]

Well this is all an incredibly pleasant surprise

[@jpjude68]

hi there :) @@Alexander-the-ok

[@AvArIeNmArKu4]

@@Alexander-the-ok love that video watched it 20 times

[@tyrantfox7801]

​@@Alexander-the-ok I just commented about in your video on the tri- propellant rocket engine.

[@JohnScherer]

Amazing job mike. I have to say, your little rope-reader device makes quick work of this.

[@antronargaiv3283]

When all you have is a rope reader, every rope needs to be read :-)

[@karlpron]

Some old tubes slowly heating up and glowing, slightly broken ventilator coming to life and buzzing in the background, some beeps, big analog dial with vibrating hand, small dial with the hand turning around like crazy - that's how Mike's contraption should look like.

[@hugodrax7111]

The second fully functional AGC in the world...? Mr Jurvetson, please, let the boys have at it.

[@vk1pe]

I am watching the movie "Apollo 13" on free-to-air TV in Australia, and watching this video during the ad breaks!

[@ksbs2036]

Oh what a treat to hear a new CuriousMarc video. Mike you are a god. I hope your deep knowledge of Apollo systems help you in your day job, but if not thank you for preserving this important part of human history

[@computer_toucher]

I never knew the invention and/or practical application of fly-by-wire was based on the Apollo program. That's a real deep cut. I love this :)

[@campbellmorrison8540]

Wonderful video. Imagine being the test pilot for those PIO tests. So good to see this stuff being saved. You guys are amazing!

[@Sjaak_PD1SRM]

great technology, state of the art then for pro's, and what you now have as a hobbyist now. what a progress in the time.

[@brauchmernet]

Oh, and Mike is just stunning. „Professional mac gyver“ if you need to describe him as short as possible

[@scsirob]

Absolute brilliance, thanks for taking us for the ride!

[@OrangeDurito]

Mike is a beast! What a glorious example of passion-driven engineering. I cannot thank you enough for this whole Apollo GNC computer series.

[@Kurgutt]

That DSKY hanging out the thing brings a smile... :) Thank you, that was fascinating ❤

[@TheJimbodean67]

I recall canada had a fly by wire plane in the late 50’s, and the f-16 is one of the first mass produced aircraft using the system. Had no idea the f-8 was an experimental platform let alone using apollo components . Cool stuff.

[@NeilABliss]

Fly by wire on the Avro Arrow

[@mikeiver]

Fly by wire is not flight control augmentation with a real time computer interposed between.

[@michaelcherry8952]

The CF-105 (Arrow) had an analogue fly-by-wire system. " This system also included solid-state components and system redundancy, was designed to be integrated with a computerised navigation and automatic search and track radar, was flyable from ground control with data uplink and downlink, and provided artificial feel (feedback) to the pilot." (Wikipedia). The F-8 was a digital system which was only possible with the "miniaturized" computers developed for the Apollo program. One of the important things the Arrow program developed was the artificial feedback for the pilots who were used to literally feeling the flow of air over the control surfaces through the stick. The lack of feedback was causing all kinds of problems in the simulator until they developed the feedback system. A lot of aerospace engineers went to work for NASA when the Arrow program was terminated. I wonder if some of them worked on the Apollo and F-8 systems?

[@NeilABliss]

@@michaelcherry8952 oh absolutely, the original comment only mentions fly by wire...not whether it was analog vs digital. Fairly certain, having talked with some of the peripheral players in the Arrow program, the flight system was good as analog, but they were aware of the potential of digital...I imagine it would have been a matter of time.

[@alexlefevre3555]

This is quite literally the only channel to which I am subscribed where I immediately click to watch the video. Work can wait. Also 12:08 has a computer looking very surprised.

[@rohit4242]

I love this guy he’s so knowledgeable on Apollo

[@_SurferGeek_]

Great to watch these pieces of historic technology being recovered and made available to all.

[@paulkocyla1343]

Running the code like seconds after having downloaded it via USB is so badass 😀 You guys are awesome. Your videos are more exciting than any action movie!

[@JonPMeyer]

At 22:20 I almost expected a CG voice to start saying: "Stop, Dave. Please stop, Dave!"

[@gnudarve]

You are the right people at the right time, standing ovation from the technical historians of the future.

[@nikreichel2232]

Thank you so much for the elaboration on the Fly by wire history (with elevator music). Those explanations in itself are a beautiful contribution to the educational aspect of a museum's work (as is the work you all do so wonderfully and dedicated). Thanks! -And hats off to the work that ran into the pocket reader! :D

[@68hoffman]

i dig steves collection and i dig even more he allows us all to see it and be used by ya'all ...amazing stuff ..amazing team :)

[@jakint0sh]

Ooh boy, it’s always a good day when you release a new video :D

[@techdefined9420]

I'm amazed by the technical prowess of your team. I wish I could study all of this collector's objects in detail, I would spend days doing so.

[@fnmatrix]

Mike is way to crazy smart

[@nmccw3245]

Amazing and brilliant work! Thank you Marc, Mike, and Ken. 👍🏻

[@guyh3403]

The pure smartness, brightness and awesomeness of Mike is absolutely from beyond this planet and really amazing!

[@jlwilliams]

Great overview of the digital fly-by-wire program! 14:58 - If you need an airplane you can bang around for research purposes, a carrier-based fighter is a good choice…

[@AsbestosMuffins]

just so happen to find another AGC lol

[@p.j.wilkins1321]

Fascinating, as always. Thank you!

[@ricinro]

This stuff will be the steam punk of the 22th century.

[@ShainAndrews]

Seriously Mike. Your efforts and accomplishments are impressive.

[@TheGunnarRoxen]

Outstanding work, Mike!

[@yce1234]

I can't press the like button hard enough! Great work! Thank you.

[@NUTTER8291]

I WE would LOVE to see if you could get a full tour of that AMAZING guys man cave !! EVEN if it is over 2 or more episodes !!!

[@CuriousMarc]

I have 3 videos of his collection already, but it would take many, many more to give his collection justice: Steve’s collection part 1: kzbin.info/www/bejne/aYqQfqKpfNh5g9U Steve’s collection part 2: kzbin.info/www/bejne/a4ulg6pmbK6VndE Steve’s collection part 3: kzbin.info/www/bejne/aYqQfqKpfNh5g9U

[@classicaudioadventures]

What a time to be alive! Hats off to Mike!

[@edmaster3147]

Fantastic as always. Can't compliment enough. Your content is a wonderful mix between tech history, storytelling, science in a narration of importance. These tales help developing a view on why and how the progress has been made. You are really good at this. Many thanks and looking forward to the next vid :), Greetings from the Netherlands.

[@SomeGuyInSandy]

Super talented team! It's fun to watch you guys noodle!

[@johncloar1692]

Nice work recovering these program. I would be sad to have lost these for ever.

[@DavidVR2]

You guys rock!👍 This series is really interesting, to be able to read and understand the code used in the Apollo guidance systems is a fantastic achievement. Please continue with this work.

[@tnmrvc]

Must've been wildly exciting back then to be working on this. Amazing tech, amazing presentation, thanks again Marc & team!

[@andrewlindh5047]

Great history lesson! Old NASA tech is just endlessly amazing for its time!

[@MichaelB-wm5cg]

I was worrying that you were going to scratch that nice wooden table top, 🤣🤣🤣🤣🤣🤣🤣🤣🤣🤣

[@SpinStar1956]

Hat's off to mike, he is one multi-talented engineer: Jack of all Trades; Master of Most!! Hope you find more Apollo stuff to reverse-engineer. How about the Saturn-V guidance and control ring? Thanks so much for all you do; absolutely fascinating...

[@kurtfrancis4621]

Excellent work, gentlemen!

[@twingoman2000]

Maik ist a Genius, love his Work!

[@Derpy1969]

I’m geeking out over you geeking out over this tech.

[@twotone3070]

As I sit here open mouthed I realise Mike is just on another plane, an F8 to be precise.

[@kerbalwww2]

Marc i can say you and you team are legends

[@tomsawyer8102]

Good on ya Mike! Keep up the great work.

[@624Dudley]

Great stuff, guys! 👍

[@MALCOLMPLUMB]

Nice video again guys.

[@thespectator2976]

Best channel for a true tech nerd :) I LOVE THIS. I learn so much history here :) and new stuff too ofc.

[@rogervanbommel1086]

Nice! Another Apollo video

[@computer_toucher]

Haha the F-8 gives me so many Boeing YF-23 hurf durf vibes :) Always did love the crusader tho.

[@rsmrsm2000]

amazing amazing amazing amazing amazing !!!

[@redace01]

Factinating as always. I'm shocked find out the AGCs were used even after the Apollo. But it makes sense, why not re-use it, if it's already been developed? Many kudos to Mike and his dilligent efforts to save and preserve this important step in our computing history. You sir are a legend! And thanks to Marc for having the camera ready and giving us the over-the-shoulder man on site view of the process. :D

[@Phil-D83]

How anything worked with the technology they had at the time still amazes me

[@scowell]

Pure alpha-nerd, bull-geek work! Thanks for assembling such a team and showing us how it's done.

Thanks for sharing.

[@paddle_shift]

ThinkPad laptops are rock solid. Best laptop.

[@mdbssn]

That last line is really the truth!

[@robinwells8879]

Possibly the coolest desk in the coolest lab ever. The world seems a little less black with minds like these inhabiting it. ❤

[@roberthopwood3758]

Mike: I'm here to read rope and chew bubble gum, and I'm all outa bubble gum.

[@RingingResonance]

NO WAYYYY!!! Dang shame the fly-by-wire ropes weren't in there. Would be really cool to have them and fly a model airplane with them. If you ever get to that point, I'm a commercial licensed pilot, and licensed UAV pilot. Would love to test fly it!

[@Graham-ce2yk]

Here's hoping someone has them in their collection and they are in good shape.

[@gavincurtis]

More people like this in the world please.

[@aaronr.9644]

Mike is a legend!

[@RA-II]

Dam I help rebuild a F8 for thunderbird Aviation in Deer-valley Airport back in the 80’s

[@ptonpc]

Amazing work :)

[@Alfred-Neuman]

Can you tell me if you can also hear something at 23:14 ? Maybe it's just my imagination but it seems like a woman is having fun in the background...

[@albertsandberg]

This is fantastic

[@brauchmernet]

Ken is right. There needs to be a more dramatic readout. Put some ws28xx on it that mirrors the progress or something. :)

[@jimmy2drinks]

Thanks guys :)

[@Nunya-py2vj]

you guys are awesome. Lets go get snoopy!

[@CuriousMarc]

Somebody convinces Elon to go get it for us!

[@Nunya-py2vj]

@@CuriousMarc they should also go get hubble. either repair it and resend it or put it in a museum. i personally think they should put it in a museum because hubble 2.0 and so on are already being drawn up

[@NUTTER8291]

Mike is the dogs ding dongs with knowledge AMAZING GUY !!

[@stokesseegers5012]

@ 15:06 Imagine being the test pilot. You're in the briefing room in the morning going over what's you're going to be doing today...

[@-r-495]

And nobody says anything about the rocks between the wooden tabletops? Love this. Stay curious!

[@CuriousMarc]

They are all meteorites. Some pretty big chunks, some pretty rare ones too. We touched a piece of Mars!

[@varjagg]

It is little known that the original assignment of R2D2 was to wander out and reprogram DSKY in the fuselage to a new profile.

[@kurtnowak8895]

Marc, you made a few passing comments on an Apollo fuel cell during a previous visit to Jurvetson’s museum. We’re all waiting for that series to drop…. 😉

[@paulcohen1555]

I like "his sticky hands" description!

[@clhoward79]

I love all you videos!! Especially this series! Have you all come down to the Huntsville Space and Rocket center? I was just there and there is an AGC there and other Apollo era electronics.

[@raymitchell9736]

Fantastic work finding these systems and recovering them. To think that this was back in 1966 and how sophisticated the systems were at that time... It seems that once the missions were over they moved on and none of this was preserved. In your video you addressed that components were reused and some software ported and used in other systems, but the legacy of these systems wasn't preserved, do you know why that was the case? I think we'd have all of it in one form or another, e.g. card decks, printouts, ground hardware? Again, fantastic work pulling this together!

[@tomschmidt381]

Great video, I had no idea the AGC was used as a test bed for early experiments in digital fly by wire. Too bad the Rope memory was not the actual F8 program.

[@jank330]

Thanks!

[@VenturiLife]

Resistors can definitely go bad, but usually after many, many years. Unusual for a resistor to fail early. You can imagine the quality control was very good for each component by NASA. Resistors tend to fail open rather than in a short.

[@genetomblin2883]

Resistors most definitely can go bad. There value can change. Their values normally go up but I had a situation once on an old ocilloscope where a large value resistor went Down. We found it and fixed the thyrotron sweep circuit.