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Lockheed SR-71A Blackbird
Originally designated RS-71, the Skunk
Works was forced to change about 29,000 blueprints to SR-71 when Lyndon
Johnson accidentally turned the letters around during his 1964
announcement acknowledging the existence of the airplane. Called the
Blackbird, the SR-71 was so far ahead of its time that to this day very
few (such as the X-15 and the Space Shuttle) airplanes can outperform it.
Everything about this airplane's creation was gigantic: the technical
problems that had to be overcome, the political complexities surrounding
its funding, even the ability of the Air Force's most skilled pilots to
master this "incredible wild horse of the stratosphere." It was a gigantic
leap over the U-2 in every way.
In the words of Kelly Johnson, "It
makes no sense to just take this one or two steps ahead, because we'd be
buying only a couple of years before the Russians would be able to nail us
again. No, I want us to come up with an airplane that can rule the skies
for a decade or more." He wanted to design an airplane that used
conventional engines and fuel, but still be able to outrace any missile.
The Blackbird, code-named Oxcart during
its development, flies on a tremendous 65,000 lbs. of thrust at an
altitude of 100,000+ feet at Mach 3.5, and has a range of four thousand
miles. That is not only four times faster than the U-2 but seven miles
higher - and the U-2 was then the current high-altitude champion. For a
long time the Air Force claimed a maximum speed of Mach 3.2 and an
operational ceiling of 85,000 feet, but we now know that the SR-71 can
soar above 100,000 feet. Some military pilots claim altitudes in excess of
125,000 feet but this is probably stretching it a bit. Compared to the
fastest jet fighter America had at the time, the SR-71 flew at least 60
percent faster than its maximum speed on afterburner. Experimental rocket
engines had flown this fast for only two or three minutes at a time before
running out of fuel. But the Blackbird can cruise at more than three times
the speed of sound, and fly coast to coast in less than an hour on one
tank of gas. The aircraft can also survey more than 100,000 square miles
of the Earth's surface in one hour. The Blackbird actually stretches a few
inches during flight, due to the massive temperatures on its titanium
hull. To many, the Blackbird is the epitome of grace and power, not to
mention blinding speed.
As of January 1st, 1997, two SR-71 air
crews and planes were declared mission ready for the first time since the
plane's retirement, seven years ago. In 1994, Congress appropriated funds
to put two aircraft back into service, and these airplanes were taken out
of storage, refurbished, and delivered to the USAF. (One was located at
NASA's Dryden research facility and the other at the Skunk Works.) These
two Blackbirds and their crews are now based at Edwards Air Force Base,
though administratively, they are part of the 9th Recon Wing at Beale.
These SR-71s are equipped with reconnaissance sensors, including the
Advanced Synthetic Aperture Radar system that provides near real-time,
all-weather, day or night imagery.
"My goal was to bring the SR-71 back
quickly, within budget, and most importantly, in a safe manner," said
Brig. Gen. Robert Behler, 9th Reconnaissance Wing commander at Beale. "I'm
proud to say we've accomplished this goal and we look forward to
demonstrating a mobility capability later this year."
Another of Lockheed's Kelly Johnson's
creations, the SR-71 Blackbird set the world speed record in 1965 and has
held it ever since. Originally called the RS-71 by Lockheed, it was
mistakenly referred to as SR-71 by President Lyndon Johnson and no one
wanted to correct him, so the SR designation stuck. The secrecy that
surrounded this aircraft was astounding, as the Air Force would never
formally acknowledge the SR-71's until well into the 1970's. The aircraft
is constructed totally of titanium alloy and incorporates original stealth
technology. The plane flew so high and so fast that many technical
problems had to be overcome during produuction. Not really black but deep
indigo blue, the paint is special, heat dissipating and radar absorbent,
as skin temperatures can reach 1100°F in flight. Heat causes the fuselage
to expand six inches in flight, requiring flexible fuel tanks. The plane
literally leaks fuel on the ground until high speeds are reached in
flight. The SR-71 uses a special JP-7 high temperature jet fuel and at top
speed needs refueling every 45 minutes. The fuel doesn't burn easily and
it takes a chemical reaction to start the engines. Cameras in the SR-71
can map 100,000 square miles in less than one, and wears out its tires in
six landings. A fighter interceptor version was contemplated, but since it
takes three states to turn around at top speed, the idea was not deemed
feasible. Upon retirement, an SR-71 was donated to the Smithsonian
Institute and in a farewell flight, flew from Los Angeles to Washington DC
in 68 minutes, again setting a world speed record. The true capabilities
of this plane may never be known since security and human pilot
limitations restrict the aircraft.
How fast does the SR-71 really
go.......?
The fastest published speed of the SR is Mach 3.5. There are several
factors that limit the speed of the SR, one is the shock waves generated
by various parts of the plane, at around Mach 3.6- 3.8 the shock wave off
the nose of the aircraft narrows enough to go into the engine, while there
is the inlet spike (which slows the air to subsonic before it enters the
engine), the shock wave bypasses the spike and causes the engine to
unstart.
Second is the heat generated by the plane moving through the atmosphere,
even titanium has it's limits, and the heat generated by the SR brings the
fuselage to the brink. Just recently I found out that during a Lockheed
Skunk Works study to see how much money and development it would take to
get the SR to go faster than it's designed top speed 3.2- 3.5, the
designers discovered (among other things) that the metal divider between
the windshield was heating up so much above mach 3.5 that it was affecting
the integrity of the windshield, and at that point they had stretched the
glass technology to the max! So Mach 3.2 to a max of 3.5.
Now according to Richard Graham: "The
design Mach number of the SR-71 is 3.2 Mach. When authorized by the
Commander, speeds up to Mach 3.3 may be flown if the CIT limit of 427
degrees C. is not exceeded. I have heard of crews reaching 3.5 Mach
inadvertently, but that is the absolute maximum I am aware of."
How high does the SR really fly, and do
the Pilot and RSO get astronaut wings after flying the SR?
The SR doesn't fly quite that high, the highest altitude I've heard
attributed to the SR was 100,00 ft (18.93 miles), all the Air Force and
Lockheed admit to is above 80,000 ft. To get astronaut wings you have to
fly at least 264,000 ft (50 miles). Which the SR (even though it's a
fantastic aircraft) doesn't get close to that altitude!
Richard Graham contributes: The SR-71s
engines require a sufficient quantity of air in order to operate. The
maximum altitude limit is 85,000 feet unless a higher altitude is
specifically authorized. Again, I have heard of crews inadvertently
reaching 87,000 feet, but no higher.
What does it cost to fly the SR-71?
There are lots of numbers floating around about how much it costs to fly
the SR, I've heard figures over $100,000 an hour to fly the SR-71, and a
$1,000,000 a picture. The figures are all over the place, it's especially
hard, because you can figure it so many different ways....do you include
Tanker support, flight proficiency ops (SR "B" model and T-38), and
numerous other expenses. I like to figure it as what it actually costs to
fly the airplane itself, no training, tanker support, etc. So with that
said.....The numbers that I've been told by people that know is $38,000
per flying hour. The costs can be lower to a rock bottom price of $27,000
per hour if the annual flying time gets above 300 hours total. So the
actual cost is probably somewhere in between 38 and 27 thousand an hour.
Well after the latest Wings episode "Spyplanes"
on recently, some interesting errors! Well here goes....
"The SR takes off with almost dry
tanks"
Well not exactly empty, the SRs tanks hold 80,000 lbs. of fuel, the SR-71
usually takes off with 45,000 lbs. of fuel on board. Not what I call
almost dry! The SR takes off with either 45,000 lbs., 55,000 lbs., or
65,000 lbs. of fuel. Almost all flights are refueled by KC-135Q's (now
"T"), there are a few exceptions though... one was called the "Rocket
Ride", which were flown from Kadena AB, Okinawa and then on to Northern
Korea, on 65,000 lbs of fuel. The only SRs that launched with a full fuel
load were the test flights from Palmdale, CA.
SPECIFICATIONS
Span: 55 ft. 7 in.
Length: 107 ft. 5 in.
Height: 18 ft. 6 in.
Weight: 170,000 lbs. loaded
Armament: None
Engines: Two Pratt & Whitney J58s of 32,500 lbs. thrust each with
afterburner
Crew: Two
Serial number: 64-17976
PERFORMANCE
Maximum speed: Plus 2,000 mph.
Range: Plus 2,900 miles
Service Ceiling: Plus 85,000 ft.
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