The SR 71 on display at Edwards had two 425's in the cart when I saw it a few years ago. They had big Holley four barrels, white painted tube headers, and a tach with a white line painted on at 4500 RPMs. The information fellow who was there said the Buicks were started and warmed up for several minutes before running them up under power.
Book .... "More than My Share of it all" .... Author .... Kelly Johnson ...... this is a great read and one of my favorites. Kelly tells of the development of the SR-71 by Lockheed Skunkworks in the late 1950's ... early 1960's . He was the Head engineer. Amazing "Old School" talent and inventiveness .... every mechanic and fabricator would love this book. ======= As far as starting turbines .... yes , many use an electric starter-generator , often powered by on-board batteries. Next time you hear a turbine start up .... the "whine" is the starter spinning the turbine .... after a few seconds you hear the fuel ignite and the turbine increases to running rpm .... flick a switch and the starter becomes a generator for the aircraft and remains engaged. ======= Larger aircraft often have an on-board APU (Auxiliary Power Unit) .... which is a small turbine powered generator .... which powers the (electric) starters on the big turbine. ===== Several years ago I saw a short video of the Buick powered start cart being used on the SR-71 ... music to a car-guys ears .... if I find the video I will post here.
If you ask me, I'd be willing to bet the airforce would maintain their engines a damn sight better than Joe Pallooka. That having been said, I'd be real surprised if theres even a grain of truth in the sellers story. He sounds like a bullshit artist.
---------------------- Ditto on both the above posts! Unless the seller can come up with some actual documentation to prove that these were actual 400 hp"SR71 Blackbird" start-cart engines., these are probably just a pair of clapped-out old Buick car engines. If that's the case - and without documentation to prove otherwise, it most likely is - they're nothing special and not worth $800 - even for the unseized one - just as cores, in my opinion. Mart3406 =============
Some aircraft even use hydraulic engine starters, with a pump driven off of an APU. It just depends on the design.
Some more info here ... http://www.sr-71.org/blackbird/startercart.php And there is a real short section of engine start in this clip (at 4:38). Looks like the carts have dual Sun 4k tach's plus some other cool gauges! http://www.youtube.com/watch?v=vtJClwKdls0
Ask him if this has anything to do with A12(early SR71) Serial #60-06931 that used to be at the NG by MSP on static display and is now displayed at CIA HQ. If he goes berzerk, you've hit paydirt. The starting solution Lockheed came up is not like other aircraft. As others have said, the J58's brought up to 3200 rpm using an external power source up through a verticle PTO shaft. The external power source was a start cart made up of Buick 425's coupled to dynaflows, paired. The dynaflows shifted from low to high while under full power. I don't know exactly why Buicks were chosen, but from what I've read and heard they were the most durable engines they tested. This is a tough life for an engine, and if you ever got to hear the start cycle in operation you would understand. At some point 425's started getting scarce, so they would substitute a 401. But a cart with a 401 would barely make the minimum horsepower necessary for ignition and the crew chiefs hated to use a crippled cart. The carts were eventually updated to 454 BBC's. But the BBC's turned out to be more fragile than the Buicks. So eventually the entire cart was replaced by an external pneumatic starter. Anyway, there was nothing special about the 425's used in the start carts. They were tuned to run on av gas, since that's what was readily available.
Exactly what I was thinking...when the A12 was on display at the Air National Guard museum, I know they had a Buick start cart to go with it.
thanks for posting that simonsez..... can you imagine running 2 425's thru straight exhaust while all that fuel is dripping out of the SR71's tanks...... more pix here..... http://www.sr-71.org/photogallery/blackbird/startercart/
JP7 has an extremely high flash point. I'd be more worried about the TEB they used for the igniter. More info: http://www.enginehistory.org/P&W/p&w_j58.shtml Thanks for posting the vid (http://www.youtube.com/watch?v=vtJClwKdls0). Rapid Rabbit was lost not long after that. Most people have no idea how incredible the entire SR71 program was.
I love this thread...I was obsessed with the SR-71 program when I was a kid...think about this for a second or two, they built these bastards at a time when in the automotive industry disc brakes, fuel injection and power steering either didn't exist or were in their infancy...and this plane not only flew faster, higher and more stealth than anything else in existence for decades AFTER it was built...I'm sure it had its flaws and quirks, but that is simply an amazing feat to me...computers? Who needs em?...
This is correct... I actually went out and got my A&P licence out of high school. I never did work in the industry but I know a little about this stuff. One of our assignments was to fire up an old Lockheed T33. I forget what turbine engines were in it but I remember the starter cart having large gauge wire hooked up to the plane.
Not sure but based on some of the articles it seems the engines were listed as having a bit higher hp rating than automotive engines. Said they were tuned to run on av-gas. I wonder if the compression was higher than normal and carburated differently? Great.... the only place I'll be able to buy fuel for this is at the airport. I'm picking up the engine / trans on Saturday and may have a bit more to share, pointing in the right direction that these are what the seller says they are.
My dad was stationed in Kansas in the late '60 . He said there was a sr71 that had problems over Arizona and needed to land. 15 minutes later it was on his runway! It was top secret so they had to leave and a secret crew came in. But that evening they had some beers with secret crew and they let them come see the plan take off. He said they started it with two big Buicks.
Another thing about these engines, if they're the real deal, they were over-maintained, undergoing a very frequent insp. and maint. program.
Now that was funny, i did not click on post, because i was not finished. Hopefully you looked at the link posted earlier. The later "Buicks" were 454 Chevys LOL.
I heard a similar story from an ex co-worker who was in the Air Force. He was a photographer stationed in Montana. He was woken and told to show up ASAP. There was an SR-71 coming from the north pole(wonder where that flight had been) with a suspected hydraulic leak. He was there to take pictures of whatever they told him to take pictures of. He said it didn't take long for the plane to get from the pole to Montana. The pilot told him the plane's altitude and speed capabilities were quite a bit more than claimed. Not long after the plane set a distance-time record that exceeded the top speed previously claimed for the plane.
I had read somewhere that the Nailheads were the only engines they could find that had the required torque across the powerband to spin the SR-71 engines. When you go to look at the engines see if there are any stampings on the block by the lifter valley cover. If you find passenger car stamping the guy is full of BS. If there are no stampings his story could be possible. But how does those two engines get from Cali all the way to MN? I guess weirder things have happened. If his story is true I want one of those 425's. My dream growing up was to fly a SR71. Unfortunately I'm both too tall and too wide to fly anything other than a chopper or cargo plane. My one friend from college that is flying fighters is a tiny little man. Powering one of my rides with an engine that had something to do with that program would be amazing.
I don't think the longblock was any different; 10.25:1 was a regular 425. It may have been recurved and jetted for the av-gas and headers, which may have accounted for the jump in hp. It's interesting to look at the differences in the photos. Some have holley's but a bunch still have 4GC's and delco distributers, which makes me think that's how they were originally outfitted. If would be great to ask Arlen Kurtis, since he's still alive. Lockheed subbed all the cart work for the entire length of the SR71 contract to Kurtis Kraft. Arlen was responsible for most of the contract, including a bunch of improvements, like the belt drive over Lockheed's design for a chain drive. It wouldn't surprise me if he's the one responsible for the weed burners and holleys. This is a guy that once held the fastest propeller driven boat record at 229mph. One thing I do miss about the cold war was the national compulsion to one-up the competition. Case in point was the time-to-climb records set by a MIG25. The AF stripped a then-new F15 of everything non-essential (down to the last 40 lbs by stripping off all the paint) picked Grand Forks in Jan. for the coldest densest air, and went after the records. They chained it to the runway, ran it up to full power, released it with explosive bolts, and in a series of runs beat every standing record up to 30,000 meters (100,000 ft.), even faster than a Saturn rocket.
The AF stripped a then-new F15 of everything non-essential (down to the last 40 lbs by stripping off all the paint) picked Grand Forks in Jan. for the coldest densest air, and went after the records. They chained it to the runway, ran it up to full power, released it with explosive bolts, and in a series of runs beat every standing record up to 30,000 meters (100,000 ft.), even faster than a Saturn rocket.[/QUOTE] That's haulin' ass!!!! I must say, that I stand ready with th "Bullshit Flag" on that one, Brother!!!!
For the sake of accuracy, it beat the Saturn to 60,000 ft (if I remember right) and broke every record set by the MIG25.
Hmmmmmm.........( he thought to himself...). I'll do a little checkin'.........I'm an old F-4 mechanic, and like that kind of stuff! It held a bunch of records for years, and may still hold some low level ones!
Let us know what codes and/or numbers are on the pad in front of the valley cover. It'll be interesting to know.
Keep in mind the avgas of that era was 110/130 octane ..... they could have run those Cart Start Buicks at higher compression ratios and temps to easily increase HP above factory (car) engines.
Another cart at an air museum in Oregon. Not pictured is the Blackbird behind the cart. I like how other descriptions provided describe the engines as tandem side by side???