SR-71 Blackbird Engine Operation Guide

This has got to be the best laymans explanation of how these engines operate...simply awesome technology!




Cheers!
OG

a reply to: OrionsGem

Best description of a jet engine I ever heard was:

Suck- the fan sucks air in.
Squeeze- the turbines compress it.
Bang- the fuel/air mix is ignited in the combustion chamber.
Blow- the air is pushed out the back.

originally posted by: Zaphod58
a reply to: OrionsGem

Best description of a jet engine I ever heard was:

Suck- the fan sucks air in.
Squeeze- the turbines compress it.
Bang- the fuel/air mix is ignited in the combustion chamber.
Blow- the air is pushed out the back.

Nah...mine is better. Its true. Reason being this is not an explanation of basic jet engine operation. This is stricly about the wonder that is the Pratt & Whitney J58.

Posting this in the aircraft forum, I assume that readers already have a grasp of basic operation.

OG

a reply to: OrionsGem

So is that. That's exactly how a jet engine works, just simplified somewhat.

originally posted by: Zaphod58
a reply to: OrionsGem

So is that. That's exactly how a jet engine works, just simplified somewhat.

Again, this is about the operation of the J58 engine during supersonic speed transitions, especially focusing on the utilization of the engine nacelles.

Do you have anything of substance to share in regards to the blackbird or its engines? Would love to hear it!

OG

a reply to: OrionsGem
A layman's reconstruction; (whew; because I thought those blue prints were destroyed years ago) and no one YET has breached the Cheyenne Mtn site cave to steal (what remain/those pristine never flown) of the 200 manufactured originals that might be stored there. I could be wrong. You never know how rumors started can result in shenanigans. Like two Pratt Whitney super sized engines could power this anomaly. Its the aerodynamics of the thing; from all profiles that are radically different (and yet it works) in 1963 the first one rolls off a production line. We were as public consumers transitioning from vacuum tube technology into transistors. Had to refuel in the air because it was so leaky during take off; joints expanded and mended when at full speed. Crazy.

a reply to: Zaphod58

I was under the assumption that a jet engine ignites fuel (bang) due to the internal heat of said engine, or is this only true of pulse jets?

originally posted by: Zaphod58
a reply to: OrionsGem

Best description of a jet engine I ever heard was:

Suck- the fan sucks air in.
Squeeze- the turbines compress it.
Bang- the fuel/air mix is ignited in the combustion chamber.
Blow- the air is pushed out the back.

Lol. Thanks.

a reply to: countingdown

A normal jet engine has a combustion chamber that has an ignition source to ignite it.

The problem with all jet engines is they can only go so fast before the air can no longer be compressed. That's where a ramjet comes in. But they only work over mach 3.

a reply to: OrionsGem

I seem to remember on the early birds (before modification) the air inlet spike had to be manually adjusted by the pilot. They lost a bird and ended up having the aero spike controlled automatically by pressure sensors or some such thing ? I might be wrong but golly gee I seem to remember that...

I would have not wanted to fly their boring missions or put up with the NSA bullsh*t but that is one bird I would have liked to take around the patch a few times !

The Aero spike was manual/hydro-mech controlled in the beginning.
Then we added teh "DEAC" Digital Electronic Aerospike Control. This was a computer to monitor the spike so as not to stall the engine.
The pilots could tell you what engine stalled by what side of thier head hyrt. It will slam into the windscreen.

Anyone wanna talk about the TEC used to ignite the augmentor?
SO much cool stuff that was designed for jus this one engine it is beyond your dreams.. but not Kelly Johnson's dreams.

a reply to: 727Sky

Unstarts were a problem until the day it retired. They put a digital control system and it kept happening.

originally posted by: Zaphod58
a reply to: OrionsGem

Best description of a jet engine I ever heard was:

Suck- the fan sucks air in.
Squeeze- the turbines compress it.
Bang- the fuel/air mix is ignited in the combustion chamber.
Blow- the air is pushed out the back.

Suck squeeze bang blow, the same as the four-stroke engine cycle.

I remember the laughter in class the day we were taught that (a while back...)!

originally posted by: DogMeat
The Aero spike was manual/hydro-mech controlled in the beginning.
Then we added teh "DEAC" Digital Electronic Aerospike Control. This was a computer to monitor the spike so as not to stall the engine.
The pilots could tell you what engine stalled by what side of thier head hyrt. It will slam into the windscreen.

Anyone wanna talk about the TEC used to ignite the augmentor?
SO much cool stuff that was designed for jus this one engine it is beyond your dreams.. but not Kelly Johnson's dreams.

I thought that it was an analong computer initially?

OG

I would also like to note that the actual flight manual for the SR71 is available online...

Here is part of the engine start up procedure:

LINK

How awesome is that??

OG

Here are a few more, highlighting the navigation and radar systems, and also the areas around the airplane which were to be avoided due to extremely high EMF radiation being emmited from the aircraft..

This is the back end of the Jet nozzle I Took at Pima Air and Space.



And here's sort of the whole bird


I thought I took more pics of the SR-71 but I guess these were the only two I took. Ill have more pic for you guys next time I go I have a membership I just haven't had the time to get back there.

a reply to: Zaphod58

Hey thanks, its one of those things that I have an interest iin but have so little time to study properly

"There is no parking brake." HA HA HA HA

Though I'm sure in every newby's excitement, even a 150 IQ whiz and maximum fighter jock could be too eager and forget.....

a reply to: mbkennel

I've lost count of the number of accidents over the years because someone who had years of experience forgot to check that the parking brake was set. Most of the time chocks stop you, but other times you end up with an extra hole in the wall and a bent jet.