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Aging U-2 Will Fight On Into the Next Decade
Hugh Pickens writes "For more than half a century, the CIA and US military have relied on a skinny, sinister-looking black jet, first designed during the Eisenhower administration at Lockheed's famed Skunk Works in Burbank, headed by legendary chief engineer Clarence L. 'Kelly' Johnson, to penetrate deep behind enemy lines for vital intelligence-gathering missions. Although the plane is perhaps best known for being shot down over the Soviet Union in 1960 with the subsequent capture of pilot Francis Gary Powers, the U-2 continues to play a critical role in national security today, hunting Al Qaeda forces in the Middle East. The fleet of 33 U-2s was supposed to be replaced in the next few years with RQ-4 Global Hawks, but the Pentagon now proposes delaying the U-2's retirement as part of Defense Department cutbacks." (Read on, below.)
Hugh Pickens continues: "The Global Hawk drone, costing an estimated cost of $176 million each, has 'priced itself out of the niche (PDF), in terms of taking pictures in the air,' says Deputy Secretary of Defense Ashton Carter. 'That's a disappointment for us, but that's the fate of things that become too expensive in a resource-constrained environment.' The Pentagon has determined that operating the U-2 will be cheaper for the foreseeable future but it won't disclose how much operating the U-2s will cost for security reasons. 'It's incredible to think that these planes are flying,' says Francis Gary Powers Jr., Powers' son and founder of the Cold War Museum in Warrenton, Va. 'You'd think another spy plane, or satellite or drone would come along by now to replace it.'"
Now why are buying cheap crap for chain the falls apart real fast in other areas?
If I remember correctly, the U-2 some years ago swapped out the original engines for essentially modified B-2 bomber engines (the F-118), which cut the fuel consumption and allowed for longer flights at altitudes above 70,000 feet. I believe that with the J57 and J75 engines, the U-2 maxed out at around 73,000 feet; the F118 could probably take it to over 76,000 feet.
There's plenty they could do differently today. Stealth technology, carbon fiber, etc. But all of that is expensive. Do you put new tires on the old Ford and drive it to work for another year, or buy a new Ferrari? Depends on your budget.
They already had a Ferrari in the SR-71, but chose to retire it and kept the old Ford.
Wow, I thought the SR-71 replaced the U-2 decades ago...
SR-71 wasn't really a U-2 replacement, just a different tool in the toolbox, that made it better suited for some tasks (getting someplace quickly and not getting shot down) and not as good at others (staying airborne in an area for a long time watching, operating within a reasonable budget). It's not surprising the U-2 has lasted so long. It was very well designed for what it does from the start, and much like the same-era B-52s we still keep flying, remains pretty damn good at what it needs to do to this day.
"Convictions are more dangerous enemies of truth than lies."
Just about everything in that sentence is wrong.
.8 and burned fuel at an average rate of 15 970 kg / hr. The 747-400 which is currently in service has a base range of 6400 NM (and up to 8000 NM for the 747-ER, nearly double!), burns about half as much fuel per hour, and cruises at about mach .85. And the 747-400 was first introduced 30 years ago! I don't have the stats for the newest iteration, the 747-8i, but Boeing claims it will be "be 30% quieter, 16% more fuel-efficient, and have 13% lower seat-mile costs with nearly the same cost per trip" than the 400.
A 747 from 1969 doesn't have the same engines as a modern 747, nor does it take the same time to fly the same distance. A 747-100 had a maximum range of 4500 NM, a top speed of mach
And that's without going into the increases in capacity, passenger comfort, and avionics that have happened in the past 50 years. This is just minor advancements on an old airframe; the biggest applications of advancements in materials science and aircraft design are for clean-sheet designs like the 787 or new military aircraft like drones.
The point of this article, though, is that the military-industrial complex's days of cozy, no-bid contracts and inflated vehicle costs are quickly coming to an end, not that we'll never be able to design better aircraft than Kelly Johnson's team did in the 1950s.
They have to call out the exact altitude and information about drift to the pilot because of the unique circumstances of landing a U-2. The U-2's wings must be fully stalled to land due to the strong ground effect generated by its wings. This, coupled with the bicycle landing gear and strong sensitivity to wind make it among the most difficult planes in the world to land. The chase car provides extra guidance without which a safe landing can have very long odds.
You can never go home again... but I guess you can shop there.
http://en.wikipedia.org/wiki/North_American_XB-70_Valkyrie
Quote: "Designed by North American Aviation in the late 1950s, the Valkyrie was a large six-engined aircraft able to fly Mach 3+ at an altitude of 70,000 feet"
http://en.wikipedia.org/wiki/Mikoyan-Gurevich_MiG-25
Quote: "The MiG-25 was theoretically capable of a maximum speed of Mach 3+ and a ceiling of 90,000 ft (27,000 m). Its high speed was problematic: although sufficient thrust was available to reach Mach 3.2, a limit of Mach 2.8 had to be imposed as the turbines tended to overspeed and overheat at higher speeds, possibly damaging them beyond repair"
Mig 25's couldn't handle doing Mach 3 for very long because their engines were made for unmanned drones, not because the airframe couldn't handle it.
What you quote from wikipedia about the SR-71 is what we are TOLD about it. The reality is that the friction heating at Mach 3+ is not a huge hurdle. The XB-70 had no extensive provisions for it. If you read more about the '71 you'll find out about the great lengths that the engineers went to to keep the skin of the aircraft and its internal systems cool- none of those are needed at Mach 3 or even 3.2, as shown by the MiG-25 being capable of 3.2 without anything unusual.
The cones on the SR-71 were there to take the '71 past what a turbojet engine can do. Read what you just posted. It bypassed the engine and went straight to the afterburners. Engineers solved the ramjet problem in the 50's man, they just stuck a jet engine in the middle of it. The maximum speed wasn't limited by the compression as quoted, it was INCREASED by it. Do you really think that the official documentation is going to say "Oh yeah we designed the engine to surpass mach 3 by a long shot"? No, because the official top speed is classified.
Now, you said name 3, and I'm going to name a plane that the SR-71 has more technology in common with than anything I've mentioned:
http://en.wikipedia.org/wiki/North_American_X-15
As an experimental plane it used heat treating with a nickel alloy to handle the speeds. How fast you say? Mach 6.72. This is the only plane I've mentioned that had to had heat treating for the fuselage like the '71 did, and it went Mach 6+
So, before you call my theory about the top speed of the '71 /nonsense/ do your homework instead of just quoting from wikipedia and going "see! it says so!"
Nobodies Prefect
Tidbits for Techs Technology Blog
As someone who flies, which usually implies taking off and landing as well, large span (>=80ft) sailplanes quite often I wouldn't want to comment on flying a U-2 in detail, but can comment a little on the long-wing-center-wheel-only aspects of the trade.
In fact, the longer the span of the wings gets, the more inertia you have around the roll axis. As a result you are much more likely to drop a wing on takeoff (which is 'run' by someone holding a wingtip for the first few seconds of the takeoff roll) when the span is rather short. The same goes for the wing dropping to the ground at the end of the landing roll.I reckon it'd be rather hard to run the U-2's wing by hand until the ailerons have some effect so they use those wheels that fall off after takeoff.
For landing sailplanes usually have quite effective airbrakes for glide path control (and somewhat counter the ground effect) that the U-2 lacks AFAIK. Given the length of typical military runways I honestly doubt that you couldn't get the thing down by simply letting the kinetic energy dissipate while flying in ground effect with the engine idle. It's rather difficult to float a certain time along the ground (no airbrakes) in gusty winds without ever accidently bumping into it so it's probably much better to stall the thing onto the ground in a controlled way and then use the wheel brake. Since in sailplanes one can do crosswind landings with up to 20 knots crosswind without too much hassle the U-2 jockeys probably could do the same and more *if* they had the same visibility through the canopy as we do. The trick is to fly with the planes nose into the wind along the runway's centerline and then 'decrab' the plane using a hearty whack on the rudder just before touchdown so that the wheel will roll along the runway instead of skidding... Probably not an easy thing to do with limited visibility and the intertia the U-2 certainly has.