XP-39 II - The Groundhog Day Thread

Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules

Status
Not open for further replies.
I had surgery last week and while waiting to be put under I noticed how bare the operating room looked. I asked the surgeon if I was getting one of these and the entire staff looked at me as if my IQ was kinda questionable

​
 
GrauGeist said:
It would seem to me, that the long-tailed version would have more stability - that is, as long as it maintained the proper CoG.
We can see how well this worked with the Me410, Meteor T.7 and flying squirrels.
Click to expand...

Yes, but the longer tail means you need more weight up front...so definitely need that nose armour. Plus you definitely want to move the radio and IFF forward as much as possible.
 
GregP said:
If there are big ears up forward, it means a loss of yaw stability that could be compensated for by longer claws on the rear paws.
Click to expand...

Are we talking rabbits or newts? Last time I checked, big ears up forward were not available as a standard fit on newts. Of course, the wonders worked by the maintenance crews, I'm sure they could have fitted the ears to newts. I'm pretty sure it wasn't a difficult modification that probably could have been done at squadron level.

Then again, a google search for newts with rabbit ears came up with this...so perhaps they were available as a standard fit:

 
GregP said:
If there are big ears up forward, it means a loss of yaw stabiliity that could be compensated for by longer claws on the rear paws.
Click to expand...
So, departing briefly from the animal kingdom, would you agree that a P-39D that weighs the same as a P-39C would climb at the same rate?
 
No, because a groundhog is heavier then a squirle. Both usa and european ones.
Now one could argue about the nuts it could carry but that would only bring beans to a breakfast.
 
P-39 Expert, not according to the tests we saw ... I still wonder about those tests. One engine was sour or one was a "good" one, or they didn't use book power, or ... hey, we went over that more than 50 pages back. There's more to the tests we have seen than is recorded in them. Thet were NOT recorded in enough detail or perhaps even correctly. I doubt we'll ever know the exact nature of the test differences.

I can speculate, sure, but that's all it would be ... speculation. I'd rather not at this juncture. Suffice to say a stock P-39 is quite sprightly at lower altitudes.

Cheers.
 
Last edited:
I say humbug. There is only one test of nut comperison but i was told by one called Nigel that the it was not a fair test.
Now we all know Nigel so there you go.
 
P-39 Expert said:
So, departing briefly from the animal kingdom, would you agree that a P-39D that weighs the same as a P-39C would climb at the same rate?
Click to expand...
Here's a serious point to consider:
Tests are tests - period.
They take one off the assembly line and put it through it's paces, recording data, listing this and that and it becomes a "pseudo benchmark".
No one took the time to record what the weather was that day, hot and humid? Cold and windy? These can affect stats.
Was the test pilot aggressive like a combat pilot? Was the test pilot familiar with the aircraft enough to know the right settings to get the most out of that particular machine?

Then on to the the real world - how will that stellar crate perform after being shot up and patched a few times?
What's the hours on the engine?
Does it have a new wing or tail cannibalized from a wreck?
Has it had a couple hard landings (which can have an effect on handling)?
Is the climate hot and humid or is it freezing temps - these extremes will have a profound effect on performance.
Are it's wheel wells packed solid with mud?
Does it have a tropical filter on the intake and is it clogged with Coral dust or Saharan sand?

There are SO many variables and combinations of variables that no two aircraft are going to perform the same out on the front lines and rest assured, they will be nothing like the clean, shiny new test aircraft back home.
Using test data for a particular type is good for having a basic idea of the type's performance perimeter, but one should never assume this is what's going to happen once it gets out to the front line.
 
Status
Not open for further replies.

Users who are viewing this thread

Total: 1 (members: 0, guests: 1)

Similar threads

S
Day fighter Ta 154
Replies
0
Views
533
spicmart
S
M
Pinnacle of Piston fighter: XP-72 vs Spiteful Mk XVI?
3 4 5
Replies
83
Views
5K
Jugman
J
M
P-39 Turbo - Here We Go Again
Replies
13
Views
2K
GregP
1937-45: Doubling down on the 2-engined 'day fighters'
7 8 9
Replies
175
Views
8K
Admiral Beez
A
P-39-style fighter by other people?
2 3
Replies
50
Views
2K
GrauGeist
Menu
Log in
Register