P51 Flap retraction time post start.

[Bert_Foster]

The Flap retraction time in both versions after start is way to long. The Flaps retract as Hydraulic pressure builds after start. In game it takes around 52 seconds. IRL it takes 12 seconds for the flaps to retract.

See this Video (from 11 seconds in) of the start process and flap retraction times:

 

Compare this to the game in the track.

 

freeflight.2022-10-21_10-52-28_00.zip

Edited October 21, 2022 by Bert_Foster

[Roland_HUNter]

Looks like it's true:

From 0:10 to ~0:21-22

[Cpt_Siddy]

It depends prolly what type of system is installed. I doubt that current bird would use WW2 stuff. 

[DBFlyguy]

 

 

 

 

 

 

DCS comparison

 

MSFS (Aeroplane Heaven P-51) Comparison

 

I think the timing in IL2 needs adjusting....

[Talon_]

On 10/24/2022 at 3:53 AM, Cpt_Siddy said:

It depends prolly what type of system is installed. I doubt that current bird would use WW2 stuff. 

 

 
WW2 footage, flaps up by the time they're visible from crank at 30:33

 

 

3:30 for landing gear doors raising after crank: 

 

[purK]

The time it takes to retract the landing gear in the P51B is also incorrect.

 

 

[SCG_Tzigy]

3 minutes ago, Krupnski said:

The time it takes to retract the landing gear in the P51B is also incorrect.

 

 

I was always wondering, takes like u can go get a beer forever

[DBFlyguy]

Oh wow.... I had no idea it was this off for the landing gear too....

 

Here's the D, also faster than in the game:

 

Example of P-51D flap raising speed and gear raising speed all in one video

 

 

Multiple P-51D's and B's showing gear raising speed:

 

 

@=FB=VikS @Regingrave would you be able to look at this for both the D and B and make adjustments?

[Sitaro]

Even if it is not realistic. Is this really a problem?  I can start the plane and taxi immediately and they are up by time I am at the end of the runway. 

 

I am all for realism. But sometimes I think we just need to pick our battles. Honestly the developers only have so much time.

[357th_KW]

There have been numerous updates over the years to do things like tweak the clocks in various aircraft.  Something like this where flap and gear actuation speed actually matters in flying the aircraft is certainly relevant.

[Sitaro]

3 hours ago, 357th_KW said:

There have been numerous updates over the years to do things like tweak the clocks in various aircraft.  Something like this where flap and gear actuation speed actually matters in flying the aircraft is certainly relevant.

 OK. All I can say is I've never had a problem getting the gear down or up in time. And the flaps are much quicker than what you get in a Bf-109. 

 

I am not really looking to argue.  It is just my personal opinion that there are more pressing issues.  That's all. 

[Talon_]

On 10/30/2022 at 7:33 PM, Sitaro said:

And the flaps are much quicker than what you get in a Bf-109. 

 

So the P-51s should be left inaccurate because the Bf109 is... realistic? Flaps in that aircraft are hand cranked.

[SYN_Mike77]

The start up time video I want to see is the P 38!  

[DBFlyguy]

55 minutes ago, SYN_Mike77 said:

The start up time video I want to see is the P 38!  

 

[SYN_Mike77]

So, slightly less than a minute between engine starts.  Now I have to get home and see what the time is in game.  Seems like it is much longer, but it might just be a perception thing.

 

Oh and thanks for the video!

[LukeFF]

On 10/23/2022 at 7:53 PM, Cpt_Siddy said:

It depends prolly what type of system is installed. I doubt that current bird would use WW2 stuff. 

 

The August 1945 P-51D manual says 11-15 seconds, so the OP is right:

 

 

Same manual -  main gear, 10-15 seconds:

 

[Cpt_Siddy]

fair enuff, i will enjoy dabbing on 109's with speedy flap BS if and when devs come around to remedy this ?

[Art-J]

About the flaps, hydro pressure seems to be the culprit. Right after engine start it builds up very slowly in GB. Once it's in the operational range, however, the flaps speed is much closer to what we see on the vids or what is mentioned in the manual. One can see it when starting the engine with flaps lever down, waiting for the pressure to go up first an then retracting them.

Edited November 28, 2022 by Art-J

[FeuerFliegen]

I notice that if I start to taxi, the flaps retract much faster than if I just leave it sitting at idle.   Maybe the 11-15 seconds is dependent upon a certain RPM, such as over 1100 or so?

 

Just like how a battery will charge faster with higher RPM (until the voltage regulator kicks in to prevent overcharging), could it be the same for certain hydraulic systems?

[Roland_HUNter]

18 hours ago, SCG_FeuerFliegen said:

I notice that if I start to taxi, the flaps retract much faster than if I just leave it sitting at idle.   Maybe the 11-15 seconds is dependent upon a certain RPM, such as over 1100 or so?

 

Just like how a battery will charge faster with higher RPM (until the voltage regulator kicks in to prevent overcharging), could it be the same for certain hydraulic systems?

You are right.

Btw: after the engine starts, the first flap closing is only the long one.
When the engine is running on idle, it's take around ~8 sec, with 30-40% RPM/GAS it's around ~7 sec.