On Sunday, January 17, 2016 at 3:27:11 PM UTC-5, amdx wrote:
I drive past the one on display in New York on the way to one of my customers. I wonder if it will *ever* stop looking like the coolest thing that ever flew?
And maybe, with the help of this exhaustive (160 pages!) book, me & the boys will get it started up and take it out for a ride.
On Sunday, January 17, 2016 at 6:45:09 PM UTC-5, Jim Wilkins wrote:
0857331566
Jim - this is a tremendous find! Now I'll be up all night reading it, but i
t ought to give me more than enough info to get the bird off the ground. Th
e really hard part is that it's on the deck of an aircraft carrier which is
, in my estimation, somewhat shorter than the required 8,500 feet to get th
e thing in the air. Of course, we could fire up the catapult, but that's a
whole other can of worms.
Seriously, though, this is going to be some interesting reading, and it WIL
L keep me up at night. Thanks for the link.
Jim - this is a tremendous find! Now I'll be up all night reading it,
but it ought to give me more than enough info to get the bird off the
ground. The really hard part is that it's on the deck of an aircraft
carrier which is, in my estimation, somewhat shorter than the required
8,500 feet to get the thing in the air. Of course, we could fire up
the catapult, but that's a whole other can of worms.
Seriously, though, this is going to be some interesting reading, and
it WILL keep me up at night. Thanks for the link.
================I wonder if the pilots really memorize and strictly observe all those
temperature restrictions and limits. The CIT limit of 427C is easy if
you're into hot Chevys but the others would confuse me, and I have
four temperature readouts visible from this chair to monitor and
respond to; indoors, outdoors, the basement wood stove and a pot
heating on it.
-jsw
Years ago I hired a (near) kid fresh out of Air Force who had served as
air traffic controller at Kadena while the Blackbirds were stationed
there. He said (amongst other stories) they had only a _very_ limited
time of a few minutes to get traffic cleared and them off the ground
before they leaked so much fuel they wouldn't have enough to get to the
refueling rendezvous point. It took getting to airspeed and resulting
friction heating to expand and seal the tanks, apparently.
I'm not sure about that. While I wasn't in the SR-71 Squadron at Beal
we did do a certain amount of support work for them, and our Squadron
Commander even went through the up-grading program and was qualified
on them. I never heard that they allowed fuel leaks.
But, depending on a lot of things they might have been taking off with
minimum fuel which would limit their time on the ground.
Well, I always wondered but he swore was true. So, I just did some
looking and whaddya' know...
"In order for the SR-71 to fly the worldwide missions, it has a special
fleet of modified KC-135Q tankers for refueling. SR-71s run on JP-7
fuel, that fills the six large tanks in the fuselage. The component
parts of the Blackbird fit very loosely together to allow for expansion
at high temperatures. At rest on the ground, fuel leaks out constantly,
since the tanks in the fuselage and wings only seal at operating
temperatures. There is little danger of fire since the JP-7 fuel is very
stable with an extremely high flash point."
From the page at
<http://www.sr-71.org/blackbird/sr-71/ > But, depending on a lot of things they might have been taking off with
...
He said when it came time to roll 'em out, _everything_ else other than
perhaps an immediate emergency landing took second fiddle 'til they were
airborne (and if that aircraft could make one more fly around, it'd
probably wait, too! ;) ).
Having been an air traffic controller, his tendency to not hesitate in
making a decision was certainly quite out of the norm of most young
engineers who had just graduated and taken their first employment (he
had dropped out and done his tour prior to returning to school and, this
time, doing well in getting his degree with honors). I became quite
accustomed to "Please stand by!" when he was engrossed in a task and I
wanted something. :)
Yes, I read that but when the SR's first came to Beal the squadron was
not fully manned and we (SAC) provided some basic support -
sheetmetal, welding, machine shop, hydraulic, etc. What the A.F.
called Field Maintenance. I have been near them when they start but
never say any fuel drizzling out of them. But, they did fly a lot of
short, say 30 minute, flights which would mean that they had a very
small fuel load aboard. The Take off, climb to altitude and refuel was
a fairly standard technique as a jet engine uses a huge amount of fuel
at low altitudes so taking off with a very light fuel load and then
refuel at some intermediate altitude was pretty standard. The B-52's
did it on all long missions and I assume that is what the SR's did
also as they flew Beal to Okinawa in one jump.
Not to make light of anything but controlling the local flight pattern
is a pretty routine practice. When the U-2's landed or took off they
cleared the pattern and the main runway had pickup trucks running up
and down it. When the F-4's practiced tail hook landings they cleared
the pattern, when the B-52's took off, one airplane every 60 seconds,
they cleared the pattern.
On the ground the tanks leaked. They took off with nominal fuel and
filled to full after the liftoff and at that level nominal leaking
and at flight altitude there wasn't leaking. It was the design. At
the flight characteristics, something had to give - design for flight
to get the full bore ability. If not - altitude would cause leaks.
I got to be within maybe 50' from a U2 that landed in a Typhoon. Made
it's run but the return was limited to our tiny island. They took off
the wings and took it home in a C-130 as I recall.
Martin
On 1/18/2016 6:42 PM, John B. wrote:
On Wed, 20 Jan 2016 21:22:24 -0600, Martin Eastburn
But, the SR's flying out of Beal made some short training flights
where they didn't do any in flight refueling. My Sgdn. Commander who
went through the "up-grade" scheme that gave other pilots the chance
to fly and theoretically qualify, in the SR, said that he made 30
minute training flights. No refueling.
It wasn't altitude that made the fuel cells leak it was temperatures.
I think that the take off and inflight refueling routine was more
likely for longer flights. As I said, they took off from Beal and
landed at Kadina, which is a longish flight.
I was at two bases where U-2's were stationed and they are a really
close mouthed bunch. Keep the airplanes in the hanger and only let
them out when they are flying :-)
One of the ground crew did tell me that preparing for a flight is a
several hour long procedure as the pilot first makes his preflight
inspection and then gets suited up and has to spend an hour or more
breathing "pure oxygen" to purge nitrogen out of his blood. then he
can go fly.
The ground crew guy said that the pilots get rather short tempered
going through all that :-)
There is an SR-71 at the Boeing Air and Space Museum in Seattle. It is
actually a variant, made to carry a drone on top. My brother and I
went on a "tour" of the plane several years ago given by one of the
SR-71 pilots. He told us that the planes did indeed drip fuel when on
the ground and cool. He told the tour group about how the plane was
fueled for spy missions. The engines the plane used were designed for
use in a boat, not a plane. But they had the power neded so the CIA
employed designers chose those engines. They still needed many
modifications though. The fuel used for the missions served three
functions. Besides fuel it was also used as the hydraulic fluid and as
a coolant for the aircraft, the cockpit in particular. Before a
mission a refueling plane was sent up to a high altitude where the air
was really cold. It then flew around for a time in order to cool the
fuel load. On the ground the SR-71 was lightly fueled with some sort
of conventional jet fuel. When it was airborne the tanks were filled
with the special fuel the plane needed to operate at the high
temperatures it was heated to. The fuel was very hard to ignite. The
pilot told us that just switching over from regular jet fuel to the
special stuff while the engine was running would not ignite the
special fuel. So a small cannister, I think he said it held a pint, of
some sort of hypergolic fluid was used to ignite the operating jet
fuel. Just a little was used each time the engines needed igniting,
around an ounce I think. The pilot told us that the skin of the
aircraft around the cockpit was heated to 650 degrees, which shows why
it needed cooling. Other parts of the skin were heated to much higher
temperatures. Behind the engines, in the exhaust path, the skin was
not a titanium alloy, but was instead some sort of nickel alloy
because this area was heated much hotter than the titanium alloys
could endure. Interestingly, much of the titanium for the skin came
from the USSR. At the time these planes were first built the USA
didn't have the skills yet to make the titanium alloy sheet needed. So
the CIA purchased the titanium sheet through several devious channels
so that the USSR wouldn't find out it was supplying the USA. The pilot
told us that none of the SR-71 aircraft were shot down. He also told
us that the pilots could watch missles on radar approaching the
aircraft and then falling short and missing. Oh, he also told us that
the top speed was still classified and that the SR-71 was still the
fastest jets made.
Eric
On Thu, 21 Jan 2016 10:41:29 -0800, snipped-for-privacy@whidbey.com wrote:
Great description, Eric. Just one correction: The P&W J58 engine was
designed for use in a jet-powered flying boat, not actually a boat.
"J58" is a navy designation, which may have led to some confusion.
I forget the designation of the flying boat, but it was dropped when
submarine-borne ballistic missiles became available. It was to be a
high-speed, low-altitude nuclear bomber.
Ballistic missiles obsoleted many other clever advanced developments.
Canada still blames us for the cancellation of their Avro Arrow bomber
interceptor, ignoring that we abandoned substantially higher
performing planes:
https://en.wikipedia.org/wiki/North_American_XF-108_Rapier
https://en.wikipedia.org/wiki/Lockheed_YF-12
I was drenched by the launching splash of this early missile sub,
another dead end:
https://en.wikipedia.org/wiki/USS_Growler_ (SSG-577)
-jsw
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