I would like to build a winch to tug 15 to 20 meter gliders into the air. 350 to 400 HP is about ideal, and slow spool-up is NOT a problem (actually a plus).
Is it reasonable to expect to reliably get that kind of power out of a P-pumped 12v without internal mods (like super studs and o-rings)? Duty cycle would be power on for about 2 minutes, with 5 - 10 minutes between launches. One nice thing is that it doesn't have to fit in a pickup truck size engine box.
TIA

 

would it still be in a vehicle or stationary type mount...a 12 v with that light of work load should last forever, i would think so atleast

 

It would be mounted to a trailer. Although I was considering finding a beat/rusted out Truck 12v Auto trans 4x4 and using the main drive shaft to power the winch. It could be disengaged for movement, and the truck put in 4wd, then driven as a front wheel drive vehicle the short distance to our lauch site. I still like that idea, (even though the 'driver' would be facing the wrong direction) but also really like idea of having lots of space of an un-covered motor.

 

so basically a huge slingshot, kinda what they use on aircraft carriers to help launch the fighters...you really think you'll need 400 HP to thats gonna be like 1000ft lbs of torque...

 

Yes. The key to high launches is delivering the maximum tension allowable for any given glider. A commercially available Hydrostatic winch uses a Cummins QSL9 (8.9 liter, 400 hp), and the test pilot says he could use more power for the larger/heavier gliders. With 5,000 feet of 5/16" plasma (spectra) rope, they consistantly get 2,000 foot launches. I'm unwilling to spend the money for a brand new motor, and my club doesn't have any really heavy gliders that would need the 8.9, but a somewhat bombed 12v might work just fine....I think.
http://www.hydrowinch.com/site/

 

you got any videos of that?? That sounds like a fun ride

but yes a 12 valve would be great for that application, simple hook up to get it running basically only need a charged battery and it will give you alot of power...

 

I can't access YouTube from here, but if you go to YouTube and search "Glider Winch Launch" I think you'll find several.
I've never winch launched, but our club does "auto" tows a couple times a year. It IS pretty cool to pitch up to a 45 degree climb and kite up into the sky. From talking to other pilots who HAVE winch launched it's similar, but much quicker. We do our auto-towing on a nearby dry lakebed, and with my truck, the limiting factor is traction. I have to be in 4WH to provide adequate acceleration for a safe launch. It's a lot of fun, but I spend the next 3 weeks cleaning my truck!

 

thats pretty cool really the only thing you need electrical on it would be the starter and then just use the mechanical shut off and i think that 400 horse would be real easy to get an hx 40 and some 215 injectors with pump work and right there is your 400 horse

 

Our engines were originally designed for irrigation so I don’t see reliability being an issue at all.

 

That's the sort of information I was hoping to find. Thanks! Now, to make my total ignorance of 12 Valve terminology public, is the P7100 the "inline" or the "rotory" pump. I have read just enough to know that the P7100 is what I want, but some sellers just note their engine as having an 'inline' pump, etc.
Thanks again.