.speed questions

[mtnman]

hmmm I always thought it was the best climb speed / rate for each individual aircraft type....... whether it is a fighter or a bomber .......

hitting ALt X will show you what the default   climbspeed is for each individual aircraft you fly, AKHog  

can anyone concur?

It does vary a bit, but each aircraft type seems to "share" a preset auto-speed.  All the F4U's are preset to 154.  The Jugs are set to 159(?) P51's at 175 (as well as the P38's).  Auto-speed pays attention to indicated speeds, not actual.

I always understood the preset speed to be set at the (approximate) speed that gives the plane the best climb rate.  The actual rate of climb will change with altitude and load-out though.  The actual angle of climb/descent will also change over time as this setting is used.  As you climb higher, you'll climb at a slightly/slowly reducing angle to allow the plane to maintain the .speed set by you or by default.  If you climb high enough with the default auto-speed you "should" actually end up in level flight.

There was a thread about gliding distance (long ago), and it was shown that the best glide speed (for max distance) was the preset/default auto-speed as well.

There are a few strategic "tricks" that go along with this setting.  As Chalenge mentioned, some set it for best corner speed (I'm not sure how effective that one is).  It works nice for bombers if you set it at a higher speed than you can climb, but slow enough to not rip your wings off.  That way you can "auto-dive" at say 300mph, while you're in the tail guns.  This has a nice effect of causing many fighters to loiter behind your tail for a nice shot.  Just make sure you keep an eye on the ground....

I'll use .speed 300/350 occasionally in my F4U, but don't find a ton of use for adjusting this from default (in my own flying).

As for the "reset" question- if you adjust your auto-speed speed, it will reset back to default when you end sortie.  This setting isn't "remembered" by the game the way .sortie and .salvo settings are...

[Stoney]

In-game, default alt-x is an approximate Vy for all aircraft.

[AKHog]

There was a thread about gliding distance (long ago), and it was shown that the best glide speed (for max distance) was the preset/default auto-speed as well.

Thats probably because max L/D is closely related to Vy. I believe if you don't account for prop efficiency then they are essentially the same.

The main reason I posted this thread is I wanted to see if all aircraft were set at default for Vy. (And I didn't want to take the time to test each one).

So far nobody has given me anything solid. Stoney says its "approximate Vy", I'm not sure what that means.

If they are not set at Vy, then finding it could make a [small] difference when you are climbing out to intercept.

[Stoney]

There was a thread about gliding distance (long ago), and it was shown that the best glide speed (for max distance) was the preset/default auto-speed as well.

I did some testing with the P-47M at typical MA weights and found that the best glide speed was a good bit higher than alt-x speed.  Now, for a SWAG, alt-x is close enough that it won't make a huge difference over short distances, but there was a difference.

Best glide in the Jug was about 175-180 IAS with the prop feathered.

http://bbs.hitechcreations.com/smf/index.php/topic,276974.0.html

[Stoney]

So far nobody has given me anything solid. Stoney says its "approximate Vy", I'm not sure what that means.

Because Vy changes depending on altitude.  In your Cessna 172 that doesn't make it above 10,000 feet regularly, a single value gets you pretty close.  But for a plane that has a critical altitude of 34,000 feet, the speed will change.  The 160 that AH2 has as the default is a compromise, that gets you relatively close to Vy.  The book values are similar, but different--within +/- 5mph...