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F-117A Stealth Fighter Retired

zonker writes "Nearly 30 years ago Lockheed Martin's elite Skunk Works team developed what would become the F-117A Nighthawk Stealth Fighter. A few of their earlier projects include the SR-71 Blackbird and U2 Dragon Lady spy planes. Today is the last for the Stealth Fighter, which is being replaced by the F-22 Raptor (another Skunk Works project)."

30 of 476 comments (clear)

  1. Re:Fuel leaking SR-71's by Z00L00K · · Score: 4, Informative

    No - it wasn't the vacuum it was the heat from the drag caused by the supersonic speed that heated the plane enough to stop the leaks.

    --
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  2. Don't worry about it... by thewils · · Score: 4, Funny

    I'm sure it will retire to a nice well-paid job in the defense industry.

    --
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  3. Re:Fuel leaking SR-71's by Thelasko · · Score: 4, Informative

    They leaked fuel until the heat caused by friction (like on the space shuttle) made the panels fit together by thermal expansion. The fuel was also very difficult to ignite.

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  4. A good plane by Protonk · · Score: 5, Interesting

    The F-117 has a great history and it will be interesting to see it go. I'm not normally the military tech-fetishist type, but this was a supremely odd creature that got to fly. Embodied in this plane are so many examples of ingenuity and hubris, it makes a good vessel for late 20th century american history.

    We developed this plane in secret, with borrowed theories from the russians. The plane itself came out of a corporate Manhattan project, built by a combination of old salts who could wave their hands and make grumpy generalizations about engine configuration that hours of calculations would bear out and younger engineers employing technology that wasn't readily available outside the united states.

    It was kept secret until we felt the need to unveil it as the epitome of american superiority in Panama and the gulf war. We spent a decade lauding the precision strike capability, ignoring reports that smart bombs were only so smart. Only in the past 5 years have we grudgingly come to accept that there were limitations to the strategy of aerial bombardment, limitations that hampered our ability to fight and killed civilians on the ground. But that doesn't make this plane or its pilots evil or murderous. We just became caught up in the technology, the gritty night vision cameras resulting in static filled screens where buildings used to be.

    In a lot of ways, that is similar to our love affair with this plane. Ugly, but elegant. Unflyable without computer aided control but possessing strangely beautiful lines. Born of american ingenuity and sullied by hubris. It is a wonderful aircraft, and a great story. Thanks to the men (and women) who built it and flew it throughout the years.

  5. Re:I still want to know... by bigkahunafish · · Score: 4, Informative
    the theories regarding this are two-fold...

    First, fighters generally attract the better pilots than bombers, and since the F117 was a first strike or tactical strike craft, good pilots were of utmost importance...

    Second, naming it as a fighter helped with the secrecy surrounding its true capabilities and use, especially in Cold War times...

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  6. Re:What are they working on now? by TellarHK · · Score: 4, Insightful

    Knock your SR-71 design estimate back about a decade. The OXCART contract that created the SR-71 (evolving it from the A-12) was awarded in 1959, so all the real design work was done before 1960, it was just the construction that took a couple years. And the SR-71 served damn well until we put enough satellites in the sky to cover things almost as well with closer to realtime monitoring.

    Sometimes it makes you wonder just how many eyes the military really has up there now, if they were willing to mothball the SR-71 with no (public) clear successor.

  7. Re:'Fighter?' by smooth+wombat · · Score: 4, Informative
    Yes. So far as I am aware, it was never designed for air-to-air combat. Rather, it was to be used as it was in the first days of the 1990 Gulf conflict during Bush I's tenure: to hit high value, heavily defended targets.


    More information on the role of the F-117 can be found at Frontline, AirToAirCombat.com, FAS as well as other sources on the intertubes. Last link has pictures of the aircraft as well as pictures and a non-Flash video of the aftermath of the only F-117 to ever be shot down. In this case, over Serbia.

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  8. Re:Fuel leaking SR-71's by UnknowingFool · · Score: 4, Interesting

    Also the SR-71 would have only just enough fuel to take off and revendevous with a jet tanker as soon as possible.

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  9. Re:What are they working on now? by PortHaven · · Score: 4, Interesting

    Nah....

    The F-22 is the real "stealth fighter". The F-117A was the stealth attack craft/tactical bomber.

    Fighters usually aren't all that super secret. But reconnaissance, and strategic assault vehicles. Now those are secret.

    The F-117A's mission is likely to be super-seded by unmanned stealth drones.

    The SR-71 was retired a while back. The F-117A was NOT a replacement for the SR-71. Rather, both operated concurrently for some time.

    The mostly likely replacement for the Blackbird is the Aurora project. Sometimes caught by seismologists and observers. Rumored to use a a pulsating scramjet and being the mach 5-8 range.

    Then there is the B2 (flying wing) bomber and the B1-B The B1-B being famous for numerous crashes. Though very few in later years. What was the change? The government had been only doing 85% of the maintenance recommended for the bombers by it's manufacturers. They began doing the full maintenance recommended maintenance, fluid changes, etc. Things ceased failing...go figure.

  10. USAF Deception by tjstork · · Score: 4, Interesting

    Actually, just the F117 Night Hawk is a bomber as far as I know

    The F- designation was actually deliberate. The USAF didn't want enemies to know that this was a bomber, not a fighter, so they named it differently.

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    1. Re:USAF Deception by Nimey · · Score: 4, Informative

      Numbers restarted from 1 starting in 1962, when the Navy and Marines switched to the Air Force's style of aircraft designations.

      Prior to that, a fighter might be designated F8U-3 -- that breaks down to Fighter, Design 8 from Vought (Vought's code was U), 3rd revision. Under the new designation system, that'd be the Vought F-8C Crusader. If it was the first design of a particular type from a company, it'd lack the middle number, e.g. the Douglas AD-2 Skyraider, which was later known as the A-1B Skyraider.

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  11. Re:I still want to know... by mgabrys_sf · · Score: 4, Informative

    Um - no it doesn't "make the radar bounce back". Radar works by bouncing back a signal to detect. Meaning if it did - it wouldn't be invisible at all - it'd be working with radar just dandy. It deflects the radar's signal to produce a much smaller return signal. Meaning it was never "invisible" but had a small enough cross-section to be regarded as a non-threat.

  12. Re:Deprecated Warfighting by hcdejong · · Score: 4, Interesting

    Count on the F-22 having better radar stealth than the F-117. The F-117 fell victim to Moore's law: During its design, all the engineers were capable of simulating (for stealth characteristics) were flat panels, hence the faceted skin, which dictated the rest of the design.

    The size was another compromise (smaller = easier to hide), and the engines didn't have afterburners to minimise the IR signature, which meant no supersonic flight. Radar technology wasn't advanced enough to build a low-observable (or Low Probability of Intercept, LPI) air search radar, and a 1970's radar would compromise the aircraft's stealthiness even when turned off.

    Oddball maybe, but the F-117 was the best possible design with 1970s technology. To get it to work at all, everything else had to be sacrificed for the one mission that couldn't be done by any other platform: surprise attacks.

  13. Re:Fuel leaking SR-71's by Frosty+Piss · · Score: 5, Interesting

    But speaking of engines, how did they keep the fuel from igniting from the engine while it was leaking?
    I was stationed at Beale and spent many nights on standby while they fueled the Blackbird. Its fuel is almost impossible to ignite without the catalyst tetraethylborane (TEB), which ignites on contact with air. There where often pools of fuel under the plane when they sat in the hangars for a few days.

    The thing that I always thought amazing at the time I worked with them was that the avionics seemed so outdated in an age where most older airframes where being fitted with glass. Lot's of round gages and such.

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  14. Re:Fuel leaking SR-71's by sootman · · Score: 5, Interesting
    And AFAIK, that was by design. They knew it would expand, so they took advantage of that and optimized the plane for flight, rather than sitting on the ground, which makes sense to me. From http://en.wikipedia.org/wiki/SR-71#Fuselage

    To allow for thermal expansion at the high operational temperatures the fuselage panels were manufactured to fit only loosely on the ground. Proper alignment was only achieved when the airframe warmed up due to air resistance at high speeds, causing the airframe to expand several inches. Because of this, and the lack of a fuel sealing system that could handle the extreme temperatures, the aircraft would leak JP-7 jet fuel onto the runway before it took off. The aircraft would quickly make a short sprint, meant to warm up the airframe, and was then refueled in the air before departing on its mission... On landing after a mission the canopy temperature was over 300 C, too hot to approach.
    I could read about the SR-71 all day long. That thing was a freaking marvel in every sense of the word and there are a million neat details about it, and it's amazing to consider that it was built in the early 60s. One little tidbit you'll often hear (so it must be true ;-) ) -- "if a surface-to-air missile launch were detected, standard evasive action was simply to accelerate and climb." The freaking thing officially flew across the country in 68 minutes.
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  15. Re:Deprecated Warfighting by Darth_brooks · · Score: 5, Insightful

    Your generalizations don't quite fit here.

    True, the B-52 and C-130 are 1950's vintage *designs*, the actual airframes that are still in service are very late runs off the line. The current B-52's were built between 1960 and 1961, and the C-130's should all be post-1965 (or later). They also don't share any of the tactical missions that the F-117 performs. For example, the B-52 is a heavy bomber. It's going to drop a whole hell of a lot of metal on a target, or carry 1.5 imperial assloads of cruise missiles near a target, unload them, then head back home in time for "Lost". The C-130 has perfected the art of flying rubber dog poop out of Hong Kong.

    Now, the F-117's job is to take the first steps towards making the C-130 or the B-52's job possible. Strike missions on heavily defended targets. Given the high tolerances the skin of the airframe must meet in order to stay stealthy, normal wear and tear on the airframe (say, a wing tip that is now an inch or two higher than before thanks to a high-G turn) could negate most of the aircraft's advantage. Comparing the F-117 to anything is is comparing oranges to briefcases.

    The statement always comes up "what're they working on now? I bet they're using them thar captured UFO's and roswell alien stuff now!!!" Ummm, yeah, I doubt it. Instead of shrinking the airframe's radar signature in order to protect the pilot, they've just gone ahead and shrunk the airframe *and* the radar signature. Tomahawks, Predator drones, better satellites, and better communications between all three. That's what has retired the SR-71 and the F-117.

    I think we're finally beginning to see the retirement of some of the meat in the seat for the really, really, really dangerous stuff. You can have a $120 million dollar fighter with $3-5 million dollars worth of pilot take out a target, or $3 million dollar drone hit the same target. Even the government can do that math.

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  16. Re:Fuel leaking SR-71's by DAtkins · · Score: 4, Informative

    There was an episode of Mythbusters which, while not directly related, did show that diesel and jet fuel would not ignite even under a plumbers blowtorch.

    As always, it's the air/fuel mixture that's the important part. This does not hold for gasoline, which gives off vapors quite nicely, thank you.

  17. Ben Rich's Book Highly Recommended by Nom+du+Keyboard · · Score: 4, Informative

    If you enjoy this kind of thing, I can't recommend Ben Rich's book Skunk Works: A Personal Memoir of My Years of Lockheed highly enough.

    --
    "It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
  18. Re:Fuel leaking SR-71's by Stanistani · · Score: 4, Informative

    So, post your evidence.

    We've seen that if you have three feds in a conspiracy, one will blab to the Washington Post, so... name your source.

    . . .

    I suspect I'll be waiting a long time.

    The center tank on TWA Flight 800 was almost empty, overheated and full of fumes, and likely a spark from a poorly wired fuel sensor detonated it.

    Oh, if you were kidding, it wasn't funny, emoticon or no.

  19. Re:I still want to know... by Ungrounded+Lightning · · Score: 5, Insightful

    why are they called "stealth fighters"? They're actually a tactical bomber, ...

    When the Continental Congress put together the country's very first army, they named it the "Second Army".

    The military is about hurting people and breaking things until the other side knuckles under. As Patton pointed out this works better if few of your own guys die for their country while getting the other poor saps to die for their own. A good military operation grabs every opportunity to improve their odds, both of success and survival.

    If calling a bomber a fighter both confuses the spys and gets the best pilots to enjoy flying its exceptionally high-value missions (with support and sensor technology limited to preserve stealth), why not do it?

    --
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  20. Re:Fuel leaking SR-71's by ahabswhale · · Score: 5, Interesting

    I used to be in the Air Force and had the pleasure to watch these things launch. They took off with full afterburners and the entire base would shake from the roar of the engines. Blue flame rings would shoot many feet out the back of the engines. Watching the SR-71 take off was the most amazing thing I've ever seen and I would always stop to watch it. Others who had been in the AF over a dozen years would stop too even though they've seen it launch hundreds of times. Just an incredible and inspiring plane.

    You always knew when they were going to launch one because they would start sending out tankers (3 to 4) a good hour or so before they launched the Blackbird.

    --
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  21. Re:What are they working on now? by noewun · · Score: 4, Informative

    The B1-B also is a supersonic bomber -- I don't know if the Russkies have a supersonic bomber or not (and I'm too lazy to go check Jane's or FAS).

    Say hello to the Tu-160. And, yes, it look an awful lot like the B-1.

    Also note that the B-1B has a maximum speed of Mach 1.25 at altitude. The rapid advances in air-to-air missiles in the 1960s and 1970s changed USAF planing for bomber missions. Instead of flying high and fast (which just makes you a perfect target for SAMs unless you're an SR-71) the idea is fast and low, which is why the B-1s mission profile was changed to flying very fast at very low altitudes. Of course now the thing usually just hangs out on station waiting to be told where to drop its bombs.

    --
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  22. Re:Fuel leaking SR-71's by DynaSoar · · Score: 5, Interesting

    Also the SR-71 would have only just enough fuel to take off and revendevous with a jet tanker as soon as possible. A loaded B-52 certainly had to, but the SR-71 didn't necessarily have this profile. The only one I ever saw up close took off from our SAC base without a tanker going along. That's not to say there wasn't a tanker up there (there was another SAC base with tankers only 200 miles away).

    More curious to me was the fact that the one we refueled had two LOX tanks, contrary to the manual's statement of only one. It had the normal one under the cockpit, and a second one in the airframe between the wings/engines. I surmise the second was a propulsion system oxidizer. The JP-7 fuel being a kerosene, the combination with LOX would have given it the propulsion profile of rocket motors being used from 1945 on. As a constantly afterburning ramjet at speed, the engines could have easily been adapted to do this.

    And frankly I don't recall the one we loaded as having leaked, from hoses-on to taxi-out.
    --
    "I may be synthetic, but I'm not stupid." -- Bishop 341-B
  23. The F-22 is impressive to see by The+Second+Horseman · · Score: 5, Interesting

    Saw one at the air show in Rhode Island last year. The first thing you notice is how damn loud the thing is. Compared to an F-15, F-16 or F/A-18's I've seen at shows, it was just painful, not uncomfortable. Even good earplugs didn't really help - you really need substantial ear protection, and even then you're likely to feel it in your skull. Aside from that, the big thing I noticed was how rapidly it could change speed and its maneuverability. Compared to the older aircraft it's like watching a superball bounce around. If you had no idea that the plane existed and you saw it at night in the sky at a distance, you'd never believe it was an aircraft. The thrust vectoring looked really effective. You don't have to know a lot about aircraft to see the difference, either - you can watch an F-22 after seeing another demonstration and the difference is obvious.

  24. "replace" is incorrect by dltaylor · · Score: 4, Informative

    The F-117 and the F-22 have two completely different missions, therefore the F-22 cannot "replace" the F-117. The F-117 is a first-strike night attack bomber, deploying, mostly, precision-guided munitions. It took on roles that would have required much larger formations had they been done with the F-111 (replacement for the F-105) which had much higher visibility, so needed escorts and AA suppression. The F-22 is supposed to replace the aging, but still very potent, F-15 as an air superiority fighter, while the F-15 is shuffled off to the strike fighter role as the F-15E.

    F-22s are much more expensive than F-15s. In theory, they are able to provide more kills-per-sortie than the F-15, so we would need fewer of them. The problem with that is that, despite supersonic cruise, there is only so much airspace that an F-22 can control, so, if the missions are geographically dispersed, a larger number of F-15s can provide more coverage.

    There is no longer an opposing air force in Iraq, and the Iranians were stupid enough to buy planes from us, so they don't really have one, either. Other than the US, there is almost no long-range bomber capability, so the only remaining function for the F-22 is as an escort for B-2s on first-strike missions into nations with active fighter forces, such as Russia, China, and Western Europe (if they don't stop picking on Microsoft).

  25. Re:Fuel leaking SR-71's by pato101 · · Score: 4, Informative

    You are both right and wrong. I'll try to clarify. The heat transfer between a fluid and a solid wall happens a the viscous zone so called boundary layer, where friction happens. On the other hand, the temperature which modulates this heat transfer is the external flow total temperature which is where viscous effects are negligible.
    The total temperature is given by the compressible isentropic flow behaviour:
    Tt/Tamb = 1+ (k-1)/k*M^2, where
    Tt is the total temperature in K or Rankine,
    Tamb is the ambient temperature in same units above,
    k is the heat coefficient ratio, for the air is 1.4 and
    M is the mach number.
    Thus, for a 3.5 Mach number, the maximum for SR-71, the total temperature is:
    Tt = Tamb*(1+0.29*3.5^2)=Tamb*4.5,
    and for a Tamb of -50 degrees celsius (-58 deg Fahrenheit), becomes,
    Tt = 223*4.5=1003K = 730 deg C = 1346 deg F

    At that speed, the ambient is sooooo hot! even when the atmosferic temperature may be soo freezing!!!!.
    At the leading edge of the SR-71 wings and the fuselage nose, you reach such temperature without any kind of viscous effects; just because you stagnate the flow isentropically there: you are more right than wrong at the end :P

  26. Re:Fuel leaking SR-71's by myth_of_sisyphus · · Score: 5, Funny

    A good SR-71 anecdote. From "Sled Driver"

            "One day, high above Arizona, we were monitoring the radio traffic of all the mortal airplanes below us. First, a Cessna pilot asked the air traffic controllers to check his ground speed. 'Ninety knots,' ATC replied. A twin Bonanza soon made the same request. 'One-twenty on the ground,' was the reply. To our surprise, a navy F-18 came over the radio with a ground speed check. I knew exactly what he was doing. Of course, he had a ground speed indicator in his cockpit, but he wanted to let all the bug-smashers in the valley know what real speed was. 'Dusty 52, we show you at 620 on the ground,' ATC responded.

            The situation was too ripe. I heard the click of Walter's mike button in the rear seat. In his most innocent voice, Walter startled the controller by asking for a ground speed check from 81,000 feet, clearly above controlled airspace. In a cool, professional voice, the controller replied, 'Aspen 20, I show you at 1,982 knots on the ground.' We did not hear another transmission on that frequency all the way to the coast."

  27. Re:Fuel leaking SR-71's by DynaSoar · · Score: 5, Interesting

    You know that plane is still classified and may or may not be in use or ready for use. I'm not sure details regarding the quantity and location of lox tanks are supposed to be well known. I've no doubt it's still classified, as are many much older and now irrelevant things; I know for a fact its true top speed and ceiling still are. I also have no doubt the plane is no longer in service, having been retired 10 years ago. NASA retains two of the original trainers, the only models still living, mostly for high altitude astronomy. All the others are accounted for and in museums. Maintaining and operating an otherwise barely supported craft would be very expensive. One can now get the better results from existing orbital observation craft than the SR-71 could ever produce.

    Its reported speed of Mach 3.2 was based on an average speed over a course; that wasn't necessarily the top. A Major Brian Shul reports having sustained Mach 3.5 at 80k ft. And an ex-USAF security police enlisted reports having guarded on in Thailand, and the pilot wore astronaut's wings (USAF astronaut standard is 50 miles, or 264k ft.). The former wouldn't require the mod I described, but the latter would have. The pressure suit used would have allowed flight to this altitude. In fact it does and then some -- it is the suit worn during ascent of the Space Shuttle.

    I spoke with a colleague at another SAC base, and he "wouldn't deny" having seen one or more with this mod, but wouldn't say more.

    The Blackbird had no effective stealth capability, so if one were still flying it'd be easily seen on today's modern radar and IR devices. Space program/satellite fans would have reported seeing something fitting the profile. Although I can only surmise what the second LOX tank was for, I have no doubt that if I saw it again, and the second fill port weren't removed, I could ID it.
    --
    "I may be synthetic, but I'm not stupid." -- Bishop 341-B
  28. Re:Imperial assloads by ill+stew+dottied+ewe · · Score: 4, Informative

    A B-52 carries up to 70000lbs in bombs, so an imperial assload would be 46667lbs. A new beetle weights 2743lbs, so an imperial assload is almost exactly 17 (2005) VW beetles, not including any imperial asses (passengers).

  29. Re:Fuel leaking SR-71's by Mahjub+Sa'aden · · Score: 4, Funny

    Thank you ever so much for clarifying. I feel as if the wool has lifted from my eyes... and been replaced with bricks.

    --
    What is is all that is. Isn't that obvious?