Early research and development by DARPA led to the design and fabrication of the TACIT BLUE low observable stealth aircraft. Most notably, it was the first aircraft to demonstrate a low radar cross section using curved surfaces, along with a low probability of intercept radar and data link. As such, the DARPA TACIT BLUE Program contributed directly to the development of the B-2 Stealth Bomber so successfully deployed by the Air Force.
In the early 1970s a study by DARPA, the Air Vehicle Observables workshop, brought to light the extent of the vulnerabilities of U.S. aircraft and their on-board equipment to detection and attack by our adversaries. After the successes of the DARPA HAVE BLUE Stealth Fighter Program, DARPA initiated the TACIT BLUE Technology Demonstration Program, an effort to demonstrate that a low observable surveillance aircraft with a low probability of intercept radar and other sensors could operate close to the forward line of battle with a high degree of survivability. TACIT BLUE first flew in February 1982 and accumulated 135 flights over a three-year period.
Other technologies addressed by DARPA included the reduction of radar cross section through a combination of shaping to form a limited number of radar return spikes designed to be less detectable by ground-based radars, radar absorbent materials, infrared shielding, heat dissipation, reduced visual signatures, low-probability-of-intercept (LPI) radar, active signature cancellation, and inlet shielding, exhaust cooling and shaping, and windshield coatings.
per [DARPA — Tech Transition](https://apps.dtic.mil/sti/tr/pdf/ADA434135.pdf
TACIT BLUE was pure Tech Demonstrator whose sole purpose was to prove the overall viability and effectiveness of cutting edge technologies that were until that point more or less theoretical.
TL;DR — it walked so that the B-2 Spirit and B-21 Raider could run
Like, the main callouts above are the demonstration of low RCS using curved surfaces, plus LPI datalinks and LPI radar and that combination is critical to all modern stealth aircraft, along with quite a few modern cruise missiles.
TACIT BLUE performed the planned flight test progran, knocked it out of the fucking park, and retired.
Welcome to the plane club! There are so many rabbit holes you can go down with aviation history, it is absolutely amazing. And there are things you will never hear about because they are too secret or because the idea never left the proposal stage. Enjoy and post here often so the community can help expand your knowledge!
nevermind the weird histories etc of aircraft......theres plenty of long rabbitholes one can go on just as far as technology and engineering etc goes (if that's your thing)😂
(ive spent countless hours 'studying' up on aerodynamics and gas turbine engines etc.)
Is there a reason why the experimental demonstrators for what became the F-117 were both named with "...blue", other than the color?
Even in the book Skunkworks, Rich doesn't say why they named the project for the stealth fighter "Have Blue" and it's odd to me that the Northtrop example shared a similar name.
I'm pretty sure code names are picked at random, as you don't want someone reversing engineering the purpose of something based on the name (as actually happened to the Germans with their radio navigation system in WW2). So I doubt there's any significance to "blue," though once it was chosen they might have maintained it for LO airplanes.
It's not a pelikan tail. Pelikan tail was invented by a McDD guy, Ralph Pelikan. Pelikan tail uses hinges in the horizontal plane like an F-35 stabilator, albeit angled front to back. This is just a regular all-moving V tail. The real advantages of a pelikan tail are lower weight because you have two hinges to better distribute the loads instead of needing a large and heavy spindle. There really isn't much of a signature advantage compared to a V tail, but compared to a 4 poster, there is.
Its test pilots remarked that it was possibly the most unstable aircraft they had ever flown. Not very surprising, but it is a little amusing. This thing didn't exactly have the characteristics justifying its instability. If it was fast and maneuverable, that'd be one thing, but this goober definitely wasn't meant for that. Just stealth.
AutobotHotRod@reddit (OP)
It’s so goofy I love it
HumpyPocock@reddit
TACIT BLUE is fucking brilliant, love it.
For those who need it, context —
per [DARPA — Tech Transition](https://apps.dtic.mil/sti/tr/pdf/ADA434135.pdf
AutobotHotRod@reddit (OP)
Why didn’t they make it operational? I’ve always been wondering that
HumpyPocock@reddit
TACIT BLUE was pure Tech Demonstrator whose sole purpose was to prove the overall viability and effectiveness of cutting edge technologies that were until that point more or less theoretical.
TL;DR — it walked so that the B-2 Spirit and B-21 Raider could run
Like, the main callouts above are the demonstration of low RCS using curved surfaces, plus LPI datalinks and LPI radar and that combination is critical to all modern stealth aircraft, along with quite a few modern cruise missiles.
TACIT BLUE performed the planned flight test progran, knocked it out of the fucking park, and retired.
AutobotHotRod@reddit (OP)
Oh, okay, thank you. I just recently got into planes so pardon me 😅
werewulf35@reddit
Welcome to the plane club! There are so many rabbit holes you can go down with aviation history, it is absolutely amazing. And there are things you will never hear about because they are too secret or because the idea never left the proposal stage. Enjoy and post here often so the community can help expand your knowledge!
Foreign_Athlete_7693@reddit
nevermind the weird histories etc of aircraft......theres plenty of long rabbitholes one can go on just as far as technology and engineering etc goes (if that's your thing)😂
(ive spent countless hours 'studying' up on aerodynamics and gas turbine engines etc.)
AutobotHotRod@reddit (OP)
I intend on doing just that :)
Expensive-Yam-634@reddit
To add to the post you replied to, It also flew like shit
AutobotHotRod@reddit (OP)
Yeah, fair. I read that the flight performance of this thing was as stable as a slum house.
HumpyPocock@reddit
No worries, mate.
After all, we all have to start somewhere!
snappy033@reddit
I mean, it was operational. It did what it was intended to do - demonstrate technology and prove it out.
It wasn’t ever designed to drop bombs or go into combat.
IvyDialtone@reddit
They make extreme versions of concepts to build on theory with real data. A ton of these concepts were integrated into next gen drones and fighters.
AutobotHotRod@reddit (OP)
Fascinating stuff!
Destroid_Pilot@reddit
Great name for a JAEGER!!!!!
AutobotHotRod@reddit (OP)
Holy shit, you’re right
cat_prophecy@reddit
Is there a reason why the experimental demonstrators for what became the F-117 were both named with "...blue", other than the color?
Even in the book Skunkworks, Rich doesn't say why they named the project for the stealth fighter "Have Blue" and it's odd to me that the Northtrop example shared a similar name.
WarthogOsl@reddit
I'm pretty sure code names are picked at random, as you don't want someone reversing engineering the purpose of something based on the name (as actually happened to the Germans with their radio navigation system in WW2). So I doubt there's any significance to "blue," though once it was chosen they might have maintained it for LO airplanes.
AutobotHotRod@reddit (OP)
Yeah, it’s odd. May have to do with blueprints, but that’s a wild shot into the dark.
KokoTheTalkingApe@reddit
Always reminds me of this.
AutobotHotRod@reddit (OP)
I can’t unsee it help
KokoTheTalkingApe@reddit
Pretty on the nose, right?
AutobotHotRod@reddit (OP)
Yep.
ScissorNightRam@reddit
I do not understand the tail
Pinko_Kinko@reddit
I think it's a pelikan tail. It's similar to a V-tail. It is supposed to be better for stealth.
dynamoterrordynastes@reddit
It's not a pelikan tail. Pelikan tail was invented by a McDD guy, Ralph Pelikan. Pelikan tail uses hinges in the horizontal plane like an F-35 stabilator, albeit angled front to back. This is just a regular all-moving V tail. The real advantages of a pelikan tail are lower weight because you have two hinges to better distribute the loads instead of needing a large and heavy spindle. There really isn't much of a signature advantage compared to a V tail, but compared to a 4 poster, there is.
Hot-Pick-3981@reddit
Same. Came to comments looking for insight. Looks asymmetric?
HumpyPocock@reddit
Just the angle of the photo.
Head on — showing the (symmetrical) tail better.
Hot-Pick-3981@reddit
Awesome thank you kind sentience!
SIUtheE@reddit
More details: https://www.nationalmuseum.af.mil/Visit/Museum-Exhibits/Fact-Sheets/Display/Article/195769/northrop-tacit-blue/
buddahsumo@reddit
I’ve been up inside it at the museum.
bemenaker@reddit
I was just coming to post that. Ugly bird is on display at Wright Patt
Average-_-Student@reddit
Also known as the H.U.M.
HIGHLY UNSTABLE MOTHERFUCKER
puffball_armadillo_8@reddit
Huh, I have a lot more in common with the alien school bus than I thought
AutobotHotRod@reddit (OP)
I wholly agree lmao
TheRealtcSpears@reddit
Duckbilled Flyapus
FZ_Milkshake@reddit
A Duckbilled Flyapuss? ... Perry the Duckbilled Flyapuss!
MacroMonster@reddit
It was actually nicknamed the “Flying Bathtub”
AutobotHotRod@reddit (OP)
Those two words sum up this curious steel creature
Zestyprotein@reddit
Always looked like one of those butter dishes with a cover, to me.
theusualsteve@reddit
Id reckon theres barely any steel on this thang
Laundry_Hamper@reddit
Do you think if you go to the Northrop-Grumman visitors' centre they'd sell you a tacit blue ice scraper
AutobotHotRod@reddit (OP)
I would definitely buy that in an instant
Laundry_Hamper@reddit
"The world's first relaxed stability ice-scraper"
FiddlerOnThePotato@reddit
Its test pilots remarked that it was possibly the most unstable aircraft they had ever flown. Not very surprising, but it is a little amusing. This thing didn't exactly have the characteristics justifying its instability. If it was fast and maneuverable, that'd be one thing, but this goober definitely wasn't meant for that. Just stealth.
AutobotHotRod@reddit (OP)
So, it was a quivering mess of a stealth aircraft. Makes sense, considering it’s design
RichardsMcGhee@reddit
I just saw this weird boy yesterday!
scruffie@reddit
Did they forget to trim the flashing from the injection-molded parts?
Newbosterone@reddit
Aka the “whale” or the “alien school bus”.
wolftick@reddit
Imagine a lot more wing and you can see the family resemblance: https://imgur.com/a/pwK9Jpt
AutobotHotRod@reddit (OP)
It’s so small :3
cat_prophecy@reddit
B2 is just really big.
AutobotHotRod@reddit (OP)
And it’s awesome too.
wolftick@reddit
That's just a model tbf 🙂
AutobotHotRod@reddit (OP)
I know, that’s why it’s so cute
myblueear@reddit
This thing is cool! The world would be different had it been produced and used.
bemenaker@reddit
It is what led to the B2 and the drones we use now.
SuDragon2k3@reddit
Wasn't it a technology demonstrator, like Have Blue?
AutobotHotRod@reddit (OP)
Yes, it was.
myblueear@reddit
I think so, but ain‘t sure…
Creepy_Reputation_34@reddit
ok, who let the EW-25 out?
AutobotHotRod@reddit (OP)
Me
LeroyoJenkins@reddit
It looks like a duck, it flies like a duck...
Lauriesaurous@reddit
Looks like the mq25 ate a bus
AutobotHotRod@reddit (OP)
Lil’ hungry boi