SR-71A Cockpit View

a reply to: thishereguy

The O2 system connected to the suit, not the helmet IIRC. Cooling, and O2, and all that ran through the suit, with a heating/cooling system for the helmet.

At the very top of the canopy (look up and zoom in) is a little metal plate that reads:

MAGNETIC COMPASS MUST BE RECOMPENSATED IF RADAR TRANSMITTER IS REMOVED OR INSTALLED.

Seems like this may have been a problem, worthy of etching and tacking on a little plate to remind everyone.

Just for safety

a reply to: Zaphod58

oh ok, that makes more sense for me . knew it had to connect somewhere.

a reply to: Zaphod58

The pressure had to be run so high that if they ran pretty much anything over, they'd blow a tire.

And thats why the ramp crew walked the runway pre flight to pick up anything on it.

a reply to: intrptr

They had a car with another SR-71 pilot in it that went out to the runway with them looking for any FOD on the taxiway. He'd talk to them on the radio all the way to the runway, and would go out about 10-15 ahead of departure and run down the runway.

a reply to: Axial Leader

did you notice the little arrow scatched in right next to it? lol, wonder what's that all about?

a reply to: Axial Leader

They also had a navigation system more advanced than anything else of the time. It was calibrated to the US atomic clock, and was capable of daylight star shots.

a reply to: thishereguy

does anybody know if the inside of the canopy is made of fiberglass? because that's what it looks like to me.

a reply to: thishereguy

The inner liner was aluminum and fiberglass IIRC, it's been awhile though. The inner structure of the fuselage was more protected from heat by the fuel, and other features designed to dissipate the heat. The leading edges were the most exposed to direct heat, and as you went back the heat lessened.

a reply to: Zaphod58

ok, thanks. with aluminum . i was thinking there had to more to it, just couldn't figure out what it would be.

and also, the fuel to cool it down? high ignition point for that i'd guess or it'd boom all over the place?

lol. not really too stupid, just trying to wrap my head around this stuff. i've always found this sort of thing fascinating .

a reply to: thishereguy

Engine start was interesting. Initially they used V8 engines in ground carts to spin the SR-71s engines, later on they developed a pneumatic start cart. But to get actual ignition of the JP7, they had to inject triethylborane (TEB) into the engine, because the flashpoint was so high.

As an amusing anecdote, during engine start of an aircraft in Okinawa, the V8 cart leaked gasoline that caught fire during ignition. While the rest of the ground crew was running for firefighting gear, the crew chief picked up a broom, and started pushing JP7 towards the fire. While everyone watched in horror, the fuel went over the fire, and put it out.

SR-71 engine start

a reply to: Zaphod58





almost like looking in the belly of the beast.

a reply to: Zaphod58
And if you ever see an aircraft with wear marks on the fire handles, run like hell!

Hehe, you know you have been doing maintenance too long when you start noticing missing screws or clamps (notice the blanking fittings Zaph?), or critiquing someone else's lock wiring effort and can work out if its 28 or 32 thou wire (see over pilots left shoulder).

LEE.

a reply to: Axial Leader
Removal of a standby compass in any major aircraft can U/S the plane instantly if you don't perform what is known as a compass swing upon reinstallation. The same probably goes for the magnetic compass in the SR-71 as strong EM fields e.g. a radar transmitter, can affect accuracy until calibrated.

A few years back a colleague of mine had to perform a cockpit window change on a new type and it was the first one carried out on that aircraft series. The R&I (Remove and install) procedure in the AMM (Aircraft Maintenance Manual) calls out for removal of such things as cockpit window trims, lighted ice detectors and the standby compass. Upon reading this my colleague thought "hmmmm.... standby compass, that doesn't sound like a great idea". So he calls up our maintenance overwatch people and says, "ahhh, you really want me to do that?". Yes they said, "well its just that if we do that wont we have to do a compass swing afterwards?", he replied. No its fine, its in the manual they retorted, "ok, are you really, really sure about that?" he again asked. Yes we are really, really sure, go ahead and do it, its fine. "Ok, on your head be it" he said. Well that last reply must have got someone thinking, so they went away, did some research and then rang up Airbus and explained the situation and the engineers reticence to carry out the task step. The reply from Airbus went something along the lines of "Oh non, non mousier, eef you do zat you weel ave to perform a compass sweeng calibration no?" Ok, and what are the restrictions on that? "Oh well you weel ave to perform it aht an authorized location". Alright fine and where are those authorized locations? "Only at Toulouse mousier!" Right at that point you could probably have heard a pin drop in that office because Toulouse is in France and the aircraft was in Sydney Australia. I imagine what happened next was along the lines of "oh sh*t, somebody ring the engineer and stop him quick!" But it was too late, he had removed the compass just minutes before. Well they pulled out all the stops on this one and tried every trick in the book to get around it, they had to contact the regulator and tell them what had happened, somebody even cooked up an idea to fly the aircraft in a racetrack pattern between Sydney and Canberra in order to calibrate or prove the calibration and they even did it but to no avail, the regulator wouldn't have a bar of it and refused to release the aircraft for passenger service without a proper compass swing. In the end they managed to convince the regulator to allow them a 5 sector dispensation on an ATP to fly with a single load of passengers (with heavy restrictions on the route taken) to London and then straight to Toulouse.

I believe since then that Airbus now allow compass swings to be carried out in certain other ports provided they meet the criteria specified. However, even today if you look in the AMM for a cockpit window change of the Capt or F/O's #1 window it still tells you to take out the standby compass, even though irony of ironies you don't actually need to.

LEE

a reply to: Zaphod58

I always heard this plane leaked out of every screw hole while on the ground.

a reply to: thishereguy


Thanks so much for the tour, THG. Bumped with enthusiasm.
When things get a little mundane T&Going around DuPage
in the old Lear I whip out the A12 in my simulator.
It's even a little more unstable until things clean up around
the control surfaces-- somewhere between sloppy and suicide
for less than 5000hr. I sure do however have a lot of respect
for the guys that drove every incarnation. Kelly was a genius.
Pass the Depenz.

a reply to: Zaphod58

I thought they never did over flights of Russia?

a reply to: MystikMushroom

Overflights were ended before the SR-71 flew.

a reply to: network dude

Not just screw hole, but gap between panels, and ever other opening that there was that fuel could leak out of.

This is so cool!

Hey Zaph, do you play any flight sims?