Groundhog Thread Part Deux - P-39 Fantasy and Fetish - The Never Ending Story (Mods take no responsibility for head against wall injuries sustained)

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AHT says the P-39 engine weighed approx 1435lbs and the P-63 engine weighed 1620lbs. 185lbs difference.


Has 1660lb for the V-1710-117 (-E21) and 1450lb for the V-1710-85 (-E19).
The V-7101-81 (-F20R) of the P-51A weighed 1352lb, the V-1710-119 (-F32R) of the P-51J 1750lb.

Somehow the V-1710-121 (-F28R) in the P-40Q weighed only 1555lb!
 
I have also had access to the real aircraft, the one at the CAF museum in San Marcos. And I have seen plans and diagrams.
Really? show us some pics or measurements to counter what GregP found when he actually measured the aircraft! Plans and diagrams? Did you know what you were looking at????
 
About a month ago our friend didn't know what that meant

Maybe he'll learn something despite himself. Maybe X XBe02Drvr had a good point when he was explaining his patience upthread. As I've said, I come to this thread to learn too, and that's only because the pilots here provide a direct perspective. Thanks to all of ya for that.

His stubbornness has brought something useful to this thread, in a way he probably didn't imagine.
 
And maybe if there wasn't so many seat harness buckles...
What about changing aluminum map cases for plastic ones, like they did in the P-40? That'll give you at least an extra 30mph at 35,000ft, I reckon...
I recommend this, and I'm serious...
True, received a copy in my first year of engineering course and referred to it frequently through my apprenticeship and whilst sitting licence papers. Got a stack of the airframe and propulsion manuals on my shelf and refer to them every now and then.
 
As has been mentioned before (way, way back upthread), he should get a ride just to see what all's involved in the process.
I'd offer to do it (if he lived nearby), but my certs are way out of date and I'm a VFR bottom-feeder compared to the other drivers in this discussion.

But I am serious - this guy needs a ride to get an idea of the "hows and whys".
 
Wait a minute. Could that have been his plan all along?
 

AHT - page 193, P-39Q. "Engine 1397", - page 410, P-63C, "Engine 1710" for tabulations for Empty weight. I assume Water Injection System weight (on 410) of 50 pounds is for the tank/lines and hopefully at CG as the Water/Alcohol usable weight is 185 pounds - which I assume is at CG (best case for 'tipping' consideration as follows). Total moment arm BEYOND datum line and original Fully loaded CG is added 313 pounds (minimum) and possibly another 215 pounds (water tank+water/alcohol);

The CG for the P-39 is forward of the main gear. Correct? Why you ask? Lean back in a chair. What happens when the 'new CG' moves past the support legs? The Door Hinge Line(aft) and pilot seat back are at the approximate seat back for full internal load. ALL additional 'Engine mass' is aft of the Pilot seat and CG with V-1710-85.

It DOESN'T help to put engine auxilliary 'bits' such as Water/Alcohol or Supercharger BEHIND the Seat, BEHIND the CG for the airplane at rest, to ADD to allowable full internal load.

Imagine your new P-39 with P-63 engine/supercharger sitting on its ass in a classic three point config with nose gear dangling in he air.

If you can.
 
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If ballast was with 6 inch cannon balls this would be a major help to modellers. Lead shot and small ball bearings could be used in most scales. I am seeing lots of win-wins here.
 
I'd give you double bacon for this if possible, although I'm jealous as I'm far too snarky to create such a well thought and direct to the point post. Well done.
 

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