Aircraft AirSpeed

[Traveler]

I've attempted to fly several aircraft according to the Pilots flight manuals of the era.  Why is it that all the aircraft seem to fly off the deck at around 100 MPH.  That just shouldn't be so.

[Rolex]

Only US Army aircraft used MPH, so are you converting from knots in the manuals correctly? Are you considering the weight and historical take-off configurations?

[grizz441]

Military Power/Normal Power perhaps?

[FLS]

Traveler could you be more specific? Which aircraft, loadout, listed stall speed, suggested takeoff speed, vs in game performance?

[Blooz]

No wind to help out maybe?

[Traveler]

Only US Army aircraft used MPH, so are you converting from knots in the manuals correctly? Are you considering the weight and historical take-off configurations?

Yes, I am a certified flight instructor.  I converted the 65Knots for the F6F to75 MPH  65 X 1.15 is just a shade under 75 MPH.

It won't fly at 75.  That's just not right.  That with 25% fuel only.

[Traveler]

Traveler could you be more specific? Which aircraft, loadout, listed stall speed, suggested takeoff speed, vs in game performance?

F6F, 25% fuel only.  nothing else.  book says 65Knots, that's should be 75MPH.  

http://www.youtube.com/watch?v=hQ55LmRwkQg

[Traveler]

Traveler could you be more specific? Which aircraft, loadout, listed stall speed, suggested takeoff speed, vs in game performance?

F6F Hellcat, 25% fuel, nothing else.  should fly at 75MPH, 65Knots,

watch this  http://www.youtube.com/watch?v=hQ55LmRwkQg

[Blooz]

[Rolex]

Your question is valid, Traveler, based on the handbook. Many sources (including the pilot handbook) are not clear or consistent with aircraft configuration, weight and also whether the speeds listed are indicated, calibrated or true. Ironically, the F6F handbook is famously unclear and inconsistent about stall speeds.

Here is an original test report indicating 86.5 MPH for the F6F-5 on page 11: Link>>

[FLS]

Interesting. Power on stall speed with 25% fuel and no ammo, A/C weight 11000 lbs, My F6F-5 POH pdf lists 65 Knots IAS. My AH minimum take off speed is 73 Knots, 84 MPH at 11000 lbs. My POH pdf also has 2 conversion charts for IAS speeds listed without context. One chart says add 12 Knots at 100 Knots, the other says subtract 5 Knots at 100 Knots. Call it 8 and 3 and we get 73 and 62. I don't know if the listed speed includes the correction or which correction is correct.

Traveler does your POH list an IAS correction chart?

Edit: Power at 53".

[Traveler]

Interesting. Power on stall speed with 25% fuel and no ammo, A/C weight 11000 lbs, My F6F-5 POH pdf lists 65 Knots IAS. My AH minimum take off speed is 73 Knots, 84 MPH at 11000 lbs. My POH pdf also has 2 conversion charts for IAS speeds listed without context. One chart says add 12 Knots at 100 Knots, the other says subtract 5 Knots at 100 Knots. Call it 8 and 3 and we get 73 and 62. I don't know if the listed speed includes the correction or which correction is correct.

Traveler does your POH list an IAS correction chart?

Edit: Power at 53".

The only chart I have are for indicated airspeeds corrected to true for Altitude and temperature.

did you watch this training film?  http://www.youtube.com/watch?v=hQ55LmRwkQg 

[FLS]

The pitot tube location on the F6F required a correction chart for IAS because the gauge didn't read IAS accurately. I believe it was a placard inside the cockpit. This was not a correction to TAS. The IAS corrections for flaps up and flaps down were also different.

I've seen the video but I don't consider "about 60 knots" in a training film to be more than ballpark. It also doesn't address my question regarding actual corrected IAS vs IAS shown on the gauge.

AH roughly matches the speed listed on Rolex's link but I didn't test the weight used at the link. Also, I was watching just the main gear so my speed could be slightly low.

[Traveler]

The pitot tube location on the F6F required a correction chart for IAS because the gauge didn't read IAS accurately. I believe it was a placard inside the cockpit. This was not a correction to TAS. The IAS corrections for flaps up and flaps down were also different.

I've seen the video but I don't consider "about 60 knots" in a training film to be more than ballpark. It also doesn't address my question regarding actual corrected IAS vs IAS shown on the gauge.

AH roughly matches the speed listed on Rolex's link but I didn't test the weight used at the link. Also, I was watching just the main gear so my speed could be slightly low.

About 60 Knots  translats to about 70 MPH but I noticed that the F6F I flew with 25% fuel was about 100 MPH to get off the gound.  that's a major difference to me.

[FLS]

I don't know why you need 100 MPH and I only needed 84. That's a big difference too. You seem to have missed every relevant point I posted in this thread as well as Rolex's link.