AiResearch Garrett GTP70-9 Jet Turbine Engine 1st Start since 1973

The AiResearch Garrett GTP70-9 turbine engine was used by the Air Force to power a generator in the tail of a KC-135 refueling aircraft. I purchased this unit back in 1997 and never got around to building the necessary electrical connections to make it run until now. It is a turboshaft engine which is different from a fighter jet engine in that all of the power generated is put into a shaft for driving a generator as opposed to putting all the power into the exhaust as thrust. At normal operating speed, the output shaft spins at 6000 RPMs with the turbine spinning at 44,500 RPM. The engine only produces 70 horsepower on the output shaft.

The engine and all lubrication, fuel, and control systems are all contained within a stainless steel box so that if it catches fire, the fire will be contained inside the box and not spread through the aircraft. The engine weighs 200 pounds and is small enough to fit on a small coffee table.

I discovered during this first startup that the Speed Control Regulator has a bad diaphragm which caused the engine to only rev up to ½ of operating speed. Once I realized this, I used compressed air to CAREFULLY accelerate the engine to 100% RPMs. The engine doesn't reach full RPMs until 4:15 in the video.

This is only for hobby as I really don't have a useful purpose for it other than the challenge to make it work safely and properly. The exhaust is a simple stove pipe which I'll eventually replace with a 6" diameter pipe. I also plan to acquire additional instruments to monitor various temperatures within the engine and put all of the instruments and controls into a nice control panel. While I have complete overhaul and parts manuals, parts are pretty much impossible to obtain since these units were built in the 60's. I'm ordering some special fuel-resistant rubberized fabric to make new diaphragms for the Speed Control Regulator

I would like to have used the theme music to the original Batman TV series at the beginning of the video but I don't have permission to use it.

Category:

Autos & Vehicles

Tags:

• AiResearch
• Garrett
• GTP
• Jet
• Turbine
• Engine
• KC135
• KC-135
• Air
• Force
• APU
• aircraft
• airplane
• helicopter
• nickelback
• plane

[fmullis]

Where did you get your AiResearch Garrett? I have an AiResearch GT Continental T85-20. I purchased mine through GSA and have no manuals. I am in the process of overhauling the GT. I rebuild industrial GT's and I am looking for rebuild manuals.

[atourbillon]

@fmullis I purchased two GTP70-9 APUs from a man in Virginia who had four of them back in 1997. He gave me a copy of the overhaul manual and the one starter coupling he had between the four engines thinking that he could start his two with compressed air. I have yet to find another starter coupling.

[fmr226]

IN SOME PARTS OF VIDEO SEEMS LIKE A HANG A LITTLE OR SEEMS THAT NEED A MEAT :-) ANYWAY SOUNDS LIKE IN HEAVEN!! CONGRATULATIONS!

[yamahonkawazuki]

NICE i want one lol. but i wouldnt have it THAT clsoe to my garage though. ( in case of catastrophic problems ;)