Increasing aircraft range

[Shuffler]

The 38 has much more oil.

The loss of landing gear, a vertical stab, a pint or two of blood all add up.

Add to this the loss of fuel through the multiple airation of the fuel cells....... it is a lot of weight.

I can honestly say that the loss of all of the above has never failed to get me to a single door hangar or a tree in the middle of  a beautiful rolling field.

[MachFly]

The 38 has much more oil.

The loss of landing gear, a vertical stab, a pint or two of blood all add up.

Add to this the loss of fuel through the multiple airation of the fuel cells....... it is a lot of weight.

I can honestly say that the loss of all of the above has never failed to get me to a single door hangar or a tree in the middle of  a beautiful rolling field.

38 does have more oil but it is also a lot heavier.

Loss of gear and V-stabilizer is bad for glide because it creates drag. So your right it does add up but in a negative way. The blood that you loose stays in the cockpit so the weight remains.

Loss of fuel is good, but most of the time when you have to glide you already have no fuel. As that is the most common reason why people glide.

Trust me you would have been able to get back without loosing all that stuff.

[Shuffler]

I'd venture to say that most gliding is for loss of oil/engine damage rather than fuel.

Less items stuck out into the air means less drag (stab).

38s have a tube on the left side to drain blood and other liquids.

I've also found that running the blender on med-hi creates an oscellation adding to further my glide.
Note blender must be half emptied through whatever means you can find.

[whels]

you have to know ur engine in the plane also. example, R2800s in P47s F6s F4Us love love RPM reduction for better fuel GPH, Manifold
change has alot lesser benefit. P51s Spits with the merlin love Manifold change but RPM has less affect. So try each and see what the
engine likes, there are some that want both. So just keep track.

[MachFly]

I'd venture to say that most gliding is for loss of oil/engine damage rather than fuel.

Less items stuck out into the air means less drag (stab).

38s have a tube on the left side to drain blood and other liquids.

I've also found that running the blender on med-hi creates an oscellation adding to further my glide.
Note blender must be half emptied through whatever means you can find.

You fly a P-38, how can you possibly be forced to glide home because of loss of oil? You have two engines. Do you stay in combat after you loose one or something?


I realize that you think that if you loose something it wont be there to make any drag. This is a common assumption but it is wrong, if you loose something that means you have non smooth surface sticking out that creates a significant amount of drag. Take a look at this picture for example:

[icepac]

That 747 went considerably faster than mach .92.......or it had explosive decompression vented into the tail structure.

[MachFly]

Here is one more picture:

[MachFly]

That 747 went considerably faster than mach .92.......or it had explosive decompression vented into the tail structure.

It lost it's #4 engine causing it to enter extreme unusual attitude, high Gs and high speed caused structural damage.



[/hijack]

[JUGgler]

It lost it's #4 engine causing it to enter extreme unusual attitude, high Gs and high speed caused structural damage.
(Image removed from quote.)


[/hijack]

I think I see a lot of poop on the inside of those windows 




JUGgler

[dtango]

Reining in the discussion back a little ....  Stoney is correct - best glide speed is typically higher than best rate of climb speed.  Power off, zero wind best glide speed occurs at the velocity where L/D is maximum.  This is typically higher than best rate of climb speed.  Best rate of climb speed occurs when Pa-Pr (excess power) is maximum which is a different than when L/D is maximum with no power available.  Why this is so requires thinking through the math of the physics a bit which I haven't done.

Here's a chart for the Cessna 172 to illustrate:

 


All bets are off when you glide in a head wind or tail wind though.

[colmbo]

It lost it's #4 engine causing it to enter extreme unusual attitude, high Gs and high speed caused structural damage.
(Image removed from quote.)


[/hijack]

The loss of the engine did not cause that problem.  The crews failure to recognize and correct is what caused the problem.

[MachFly]

The loss of the engine did not cause that problem.  The crews failure to recognize and correct is what caused the problem.

Your right, I just did not want to get into this discussion in this thread.

[MachFly]

Reining in the discussion back a little ....  Stoney is correct - best glide speed is typically higher than best rate of climb speed.  Power off, zero wind best glide speed occurs at the velocity where L/D is maximum.  This is typically higher than best rate of climb speed.  Best rate of climb speed occurs when Pa-Pr (excess power) is maximum which is a different than when L/D is maximum with no power available.  Why this is so requires thinking through the math of the physics a bit which I haven't done.

Here's a chart for the Cessna 172 to illustrate:

(Image removed from quote.) 


All bets are off when you glide in a head wind or tail wind though.

Since you brought up the 172, it's Vy is 74kts (72kts at 10K) and best glide is 68kts. Reference C-172SP NAV III POH. 

[colmbo]

Reining in the discussion back a little ....  Stoney is correct - best glide speed is typically higher than best rate of climb speed.  Power off, zero wind best glide speed occurs at the velocity where L/D is maximum.  This is typically higher than best rate of climb speed.  Best rate of climb speed occurs when Pa-Pr (excess power) is maximum which is a different than when L/D is maximum with no power available.  Why this is so requires thinking through the math of the physics a bit which I haven't done.

Here's a chart for the Cessna 172 to illustrate:

Nice chart, don't doubt it's accuracy.  I'm a long way from my 172 POH, from memory Vy is 90mph, Vbg is 80mph.  I wonder why Cessna would publish a lower than optimum glide speed?  (Although a lot of the numbers in a POH are based on more than just performance -- Vx and Vy being a couple of them with considerations being made for engine cooling, stall prevention, etc. )

[Stoney]

Colombo, if I remember correctly, you've got time in a B-24?  What was Vy vs. Vbg in it?