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Okay guys, this is a posting from a thread from a bunch of tractor guys who are iced in, in Nebraska. Tell me, is this possible, or has someone been hitting the hooch too hard?

Don't laugh.
I've witnessed a 737 "jump" start a C130 Hercules cargo plane..................... Confused
Starter was gone on one of the 4 herc engines. Parked the jet real close infront of the herc, gave the 737 lots of throttle which moved enough air to spin the prop on the herc. Got the prop spinning fast enough, started it up. Wish I had pictures
True story.Full Thread Here

"Bump" starting a turbo-prop by spinning the prop? I'd really, really like to hear from a qualified C-130 crew chief or mechanic about what's involved in that feat. Not sayin' it can't be done, but I wanna' hear it from a flight crewman, not a "witness". I'm trying to picture how you get the turbine to light up while swallowing a bunch of hot exhaust gases from the jet....and we won't even get into the attendent risks of the heat.

The "witness' has added more to the story...it happened the Arctic region.

I just read the thread and I'm skeptical. If the RCAF crew was worried about a 3 hour flight on 3 engines. If they could get in the air with only three why not take off and air start the engine. If it can't get it to air start just land and call for a maintenance crew then the possibility of damage from debris blown by a jet wash powerful enough to turn the prop is just too great besides the potential heat damage.

Hi Folks!

A long, long time ago in another world(RVN), I seam to remember a article in the local rag (Stars and Strips - Pacific) were the prop wash from one C-130 was used to jump start the engines on a second C-130 at some remote airstrip with no support.

When I first read this tail, that old story jumped to mind. If I recall correctly, there was a picture showing the tail of the working Herc almost back into the nose of the dead bird.

A very old story,
Sgt, Scouts Out!

I'm not gonna say it's impossible, because I've never tried it. But, I think I'm qualified enough to say...not a chance.

First off, there are two turbine sections in the engine, the N1 and the N2 compressors. N1 is what actually runs the prop, and is connected to it through a gearbox. N2 is a completely independent turbine which actually keeps the engine running.

In order to start the engine, you have to get that N2 turbine spinning very fast (Don't know exactly what it is for the Allison T56, but probably somewhere in the range of 5-6000 rpms). Since the N2 isn't connected to the prop, just spinning the prop wouldn't help anything.

Second, if you wanted to get the "jet wash" to turn the N2, you'd have to blow it into the intake, get it through the N1 turbine, and then through the N2 turbine, and still have it at a high enough speed and pressure to get it to spin at high enough speed And it'd have to be clean air too, not exhaust.

And third, a little bit of knowledge one how turbine engine starters work shows that the whole "engine starter not working" thing won't happen. Turbines start by taking compressed air from another engine and blowing it straight into the starting engine, which spins that engine until it becomes self supporting.

It's just a bunch of pneumatic lines. So if those things don't work, then there are larger problems than just "jump starting" the plane. It's unairworthy and won't be flying, period.

-S-

I use to cook chicken behind running jets when I couldnt afford a barbecue..

Hammer

Yea but you get a tinge of JP-4 flavor instead of Mesquite that way

- 401RCAF_Hammer

I use to cook chicken behind running jets when I couldnt afford a barbecue..

That explains yer 70's afro hair-do mate lol