Official Aviation Thread...

[einhander]

Saw this AN-12 in Bangkok a couple weeks ago. Russian C-130.

[cbouchez]

Blackbird

[E30_Pare]

If u watch that vid i posted theres a nasa pic of a blackbird bending light. Epic.


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[george graves]

That pic is amazing.....

What was the sr-71 skin made of? And why did it leak so much fuel until it was heated up? Those are fun *facts* but the engineering side of me asks "why"? Why wasn't the fuel in blatters? Anyways.....

...........................

Here's a cool vid of a B1b landing at Edwards when it's front nose gear didn't extend. Apparently they were re-directed to Edwards AFB for the dry lake bed vs going back to Texas where they came from.

******Side note.....So, my mom and dad met at Edwards air force base - way back in the day. My dad designed the liquid rocket engines for the Apollo program. And my mom was a civilian working in pool of secretaries for the solid rocket division. They even got married at the Officer's club on base there at Edwards.

My mom has a few stories of experimental planes that was a totally "hush hush", yet, they would do a fly over during a BBQ on a Saturday. And then you'd see them carried home in the back of a flatbed, in 100 parts. They lived in the offer's quarters, so they had some nice digs. But all the supersonic antics, left no plaster wall un-cracked.

So any video that is about Edwards I love to watch.

Anyways.....note the elevators when he tipped the nose down. I assume that's full extension.

I've seen a B1 at air shows, and they are HUGE. It's more of a flying building then a plane. That crew has some huge gonads.

[gkurey]

That pic is amazing.....

What was the sr-71 skin made of? And why did it leak so much fuel until it was heated up? Those are fun *facts* but the engineering side of me asks "why"? Why wasn't the fuel in blatters? Anyways.....

...........................

Here's a cool vid of a B1b landing at Edwards when it's front nose gear didn't extend. Apparently they were re-directed to Edwards AFB for the dry lake bed vs going back to Texas where they came from.

******Side note.....So, my mom and dad met at Edwards air force base - way back in the day. My dad designed the liquid rocket engines for the Apollo program. And my mom was a civilian working in pool of secretaries for the solid rocket division. They even got married at the Officer's club on base there at Edwards.

My mom has a few stories of experimental planes that was a totally "hush hush", yet, they would do a fly over during a BBQ on a Saturday. And then you'd see them carried home in the back of a flatbed, in 100 parts. They lived in the offer's quarters, so they had some nice digs. But all the supersonic antics, left no plaster wall un-cracked.

So any video that is about Edwards I love to watch.

Anyways.....note the elevators when he tipped the nose down. I assume that's full extension.

I've seen a B1 at air shows, and they are HUGE. It's more of a flying building then a plane. That crew has some huge gonads.

Yeah, the crew would be at full aft stick because when landing with unsafe nose gear, it's ideal to touch down normally on the mains and hold the nose off the ground until airflow will no longer permit so you can slow down as much as you can to mitigate damage. You only do that to a point where you don't slam it down either...if that makes sense. This is what I've been taught flying other planes anyways...no B1 training here.

Many times aircraft landed gear up can be repaired rather easily and returned to service in reasonable amounts of time. This is also likely why they wanted to do this landing in a dry lake bed instead of on a paved surface.

[BlackbirdM3]

That pic is amazing.....

What was the sr-71 skin made of? And why did it leak so much fuel until it was heated up? Those are fun *facts* but the engineering side of me asks "why"? Why wasn't the fuel in blatters? Anyways.....

...........................

The whole SR-71, YF-12, A12, M-21 was built of what is known as Beta Ti 13V11Cr3Al that is a Titanium Alloy that is comprised of 13% Vanadium, 11% Chromium, 3% Aluminum and the rest being pure titanium. Its very, very cool stuff. Check this picture out to see one of its properties...



The guy is holding a piece of Beta Ti in his hand while heating the end of it to glowing hot, talk about heat dissipation.

Here is a good pic of just how hot the surface got in flight, and where it got the hottest.


As for why the SR-71 leaks. The fuel tanks are lined with a sealant at all the joints. They couldn't use a bladder to hold the fuel because they used the fuel to help cool the surface circulating it around and more or less using the fuel itself as a heat sink. Because the airframe did grow a pretty sizeable amount when it was up to temp obviously there were going to be areas that didn't seal well when it was cold. 3M made the epoxy sealant but in 30 years of use, they never did find a flexible sealant that would hold up to both the heat and the fuel. This is also why every 9 months or so an active plane would be flown to Palmdale, totally disassembled and given a very thorough overhaul. At this time the tanks would be resealed. The worst leaking one of the bunch was 981, the two seat SR-71C that was built from the static mockup cockpit and the aft airframe of the second YF12. The two were never meant to be together, and the aft bulkhead of the cockpit section was never sealed when it was built because it was never meant to fly. The C model had a huge fuel leak from the front fuel tank because of this (It also didn't fly straight.)

Another side note, how does one eat a hot lunch while flying the SR? You put the tube of food next to the windshield for 2 min, then flip it for 2 min and eat it. The inside temp of the windshield was as hot as an oven.

Will

[george graves]

^nice post. Thanks for the explanation - I see where you're going with that. I am surprised that flying that high(with so few air molecules), would cause that much drag, and then turn that into so much heat. It's not quite re-entry kind of friction, or speed.

Plus, the frontal area of a sr-71 is about 1 or 2 piper cubs. It's a razor blade.

It's hard to wrap your head around the dynamics of that plane.....I guess that's what I'm getting at.

[10Toes]

blackbird

m-21

[henryki]

Little off topic from the SR-71 conversation. But my school received a 727 from FedEx as a donation to our flight program. It's never allowed to fly again but has been repainted and is free advertisement for the school and we can use it to learn more about the avionics in bigger aircraft. I'm just surprised that they were able to land it at Riverside (KRAL). And the school got a piper apache when they bought a hangar, it's been in there for like 20 years and the owner of the hangar didn't want to deal with selling it so he just gave it to the school.

Collegial aviation programs are amazing and I'm loving every minute of class and flight training.

[BlackbirdM3]

^nice post. Thanks for the explanation - I see where you're going with that. I am surprised that flying that high(with so few air molecules), would cause that much drag, and then turn that into so much heat. It's not quite re-entry kind of friction, or speed.

Plus, the frontal area of a sr-71 is about 1 or 2 piper cubs. It's a razor blade.

It's hard to wrap your head around the dynamics of that plane.....I guess that's what I'm getting at.

Thanks. One thing you must remember is that there is still air at that altitude and if there is air, there is friction. 2200+ mph is going to create friction. Sure, the outside air temps are close to -100 degrees F (or colder) but still, moving through air at those speeds is going to get hot. This is one of the the things the XB-70 had going against it. Sure it could dash to Mach 3 but it couldn't stay there because the stainless steel honeycomb skin would start to peel off. (There is a story about a YF12 test pilot talking to an XB-70 pilot and the comment was something to the tune of "one of our missions spends more time above mach 3 than your entire program has." The reply was something along the lines of "Yes, but we loose bigger pieces than your entire airplane."

The interesting thing about the Blackbirds is the fact that the surface of them is not at all smooth. It was discovered that due to the way the boundry layer sat, it didn't need to be perfectly smooth. They wouldn't go any faster because of the way the boundary layer blanketed the rough areas. It still acted like it had a smooth skin at speed. The only thing that held the speed to a limit was the engine compressor inlet temps. Redline on the J58 is 420 degrees C, if you can keep the engines below that, hang on. On the last flight of 972 from LA to Dulles, during the planning stages it was figured that the flight could be done in about 45 minutes, if they exceeded the redline temp. The guys at Pratt & Whitney were contacted, and they said yes go for it, what do you have to loose? Sure the engines will be toast, but its the last flight so who cares. Air Force brass got wind of the plan and very nearly killed the flight altogether because they didn't want the SR-71 getting anymore positive press (because it would make them look like idiots for retiring them.) I believe it was Senators Glenn and Byrd who made the flight happen. Do the math on the distance and time to get from LA to D.C. in about 45 minutes. Max speed of 2200 mph my ass. The flight was done in 63 min (I think)

Will

[henryki]

Saw this picture on GoPro's Facebook page for photo of the day.

This is literally exactly what I want to be doing for a living. I'd be happy as a clam being able to fly either one haha.

[george graves]

The interesting thing about the Blackbirds is the fact that the surface of them is not at all smooth. It was discovered that due to the way the boundry layer sat, it didn't need to be perfectly smooth. ...... Max speed of 2200 mph my ass. The flight was done in 63 min (I think)

Will

That's interesting. In the world cup sailing races, they use to (or still do) apply a layer of sheathing to the hull....with microscopic fingers on it(IIRC modeled after shark skin). To make a "boundary layer" of flow. Imagine tiny little circles that act as ball bearings all over the surface.

But for the sr-71.....

[cbouchez]

[Ray Smoodiver]

gurky what airport is that, I must go to where ever that place is..........................

New Zealand, the Alps somewhere, or the Eurasian mountains or something

Queenstown http://en.wikipedia.org/wiki/Queenstown,_New_Zealand

We're renting a house for two months this snowboard season :D come for a beer!

[george graves]

Since you are in Victoria, take a day and head down to the Boeing Museum of flight at Boeing field. There you can actually sit in the cockpit of SR-71 977.

Is that with general admission ticket? What' the deal on that? Do tell. Plan on taking the little lady this summer.