Landing gear drag

[OBT-Psycho]

Hi all!

I post it here so we can discuss, but there is what I found flying lagg last week.

 

As you drop the gear, you should notice a severe increase of the drag leading to a loss of speed. 

 

 

Brief description: 

Speed do not drop a lot once gear is down.

 

Detailed description, conditions:

When you plan you landing, and on the down leg of the pattern, once you drop the gear I assume your speed should decrease due to additional drag. But I experienced that the speed will only drop of some 10 or 20 kph. I am no real pilot or so, but I assume a landing gear induces more drag. In this state it is comparabble to opening the canopy. 
 

Additional assets (videos, screenshots, logs): 

I have no additional assets though. it is quite easy to test. I am not sure it is a real bug, I could be mistaken by something else, but it could be cool to have another opinion on this.
 

 

 

BTW, it seems that for instance non-retractable tailwheel leads to an increase of 10kph or so. I think there might be something going with the landing gear, as you just lose 10-20kph when it is dropped. 

I might have misinterpreted something. I came to think the speed loss may come slowly, or even the fact I was applying power might have dampened the effetc. 

 

I just one to share my view, hoping someone with aerodynamical knowledge might clarify all this to me. That beeing said, next week will help us to sort this out. but wan we please keep an eye on it?

[Furio]

Drag is not the same at any speed. At low speed, when you can lower the gear without damage, the drag is relatively low. I’m sure that game engine calculates drag pretty well!

[OBT-Psycho]

I am sure the FM is close to perfection. I've never have this feeling of a plane before. But I imagined  dropping the gear would be more costful in term of speed.

 

Seawolf  sent me this link regarding test on finnish G-2 :

http://www.kurfurst.org/Performance_tests/109G_MT215/109G2_MT215_en.html

 

 

"As a late production Bf 109G-2, WNr. 14 783 / MT-215 was fitted with an enlarged, non-retractable tailwheel as opposed to the previously retrractable one; this change caused -12km/h loss of speed at SL. This needs to be kept in mind when comparing the results with previous trials of the Bf 109G featuring retractable tailwheels."

 

I have to agree with him as he stated that if this detail about retractabe tailwheel can cost you 12kph, the whole landing gear should slows me a bit more than barely 20kph, should'nt it?

 

but once again I could have been fooled by other specific points, and that's why I am really gonna try it out as soon as servers are back on again.

 

but I was wondering if anybody has experienced the same during last week. 

 

BTW, what would be a good siuation to test this parameters? I can think of a simple one like following :

 

- try to stabilize your speed at certain speed, let say 300kph

- level your plane and keep it steady

- hit the button for landing gear and keep you eyes on both horizon and tachometer

 

I expect to see that last one decrease of at least 50kph doing so. I am not sure if it is supposed to happen right away or if it will take few tens of second here. When I do the same with flaps, this hapens in a matter of seconds, but I understand that landig gear is quite different aerodynamically speaking and then effect may occur differently.

 

Maybe someone may have a better situation to test it better? or to show it in a different way?

 

 

[Furio]

The loss of 12 kph was at maximum speed, not certainly at pattern or landing speed. Consider that drag increases with the square of the speed, and the difference is enormous. It’s not entirely correct to put it this way, but at 200 kph, the speed reduction due to the same tailwheel was way lower. Probably less than 1 kph, I think.

[Furio]

 

- try to stabilize your speed at certain speed, let say 300kph

- level your plane and keep it steady

- hit the button for landing gear and keep you eyes on both horizon and tachometer

 

 

 

Not easy to be done. The gear can be lowered only under VLO, the maximum speed at which the landing gear can be extended.

Edited November 24, 2013 by Furio

[dburne]

I certainly have no knowledge of this, but reckon maybe, with this being an alpha,  there are just some things that will be tweaked over the next few months before release?

[Furio]

I certainly have no knowledge of this, but reckon maybe, with this being an alpha,  there are just some things that will be tweaked over the next few months before release?

Surely, but I doubt that the law of physics will be tweaked. The speed reduction reported by OBT looks reasonable.

[OBT-Psycho]

As I said, I was'nt sur about how much gear should affect speed once dropped. So if you say it seems plausible how it is reflected in the sims, I am totally ok with that.

 

I got the fact that drag depends of speed and being in a landing pattern isn't the best way to demonstrate this. 

 

So afterall I guess they made it right. even more than expected. And the more we go, the more I learn about flying. a couple of hours now 'till the next lesson 

[SeaW0lf]

 

I didn't paid much attention to it, but the drag of the undercarriage was so subtil that I even deployed it above 300km/h and I don't recall seeing any substantial reduce in speed. I expected a thud or a bump, but I'll pay more attention to it with the release of the 109, but I agree that -- if this is the case -- this is just a tweak.

[SimFreak]

http://www.pilotfriend.com/training/flight_training/aero/drag.htm

 

Some very light reading.....

 

So, drop gear - add power to remain in new configuration and same airspeed.  if you do not, slower airspeed will add drag (ref to total drag chart)

[FuriousMeow]

The landing gear provides sufficient drag when little to no power is applied with the LaGG in BoS, I lost sufficient airspeed when throttle was reduced to land. Full flaps also aided in speed reduction. If you are expecting a massive reduction in speed while under even 50% power then you certainly shouldn't. Prior to landing gear being retractable they sat underneath the planes, that were very underpowered and those things managed flight from between 80mph and 180mph in the fabric and wood configuration. Even the full metal frame and stressed metal skin configurations were up into the 200s with fixed landing gear.

Edited November 25, 2013 by FuriousMeow

[SimFreak]

I don't have access to alpha...can anyone test straight and level flight and see how much speed changes?

[pixelshader]

I don't have access to alpha...can anyone test straight and level flight and see how much speed changes?

 

when the servers come up tomorrow

[Kurfurst]

... and also, downthrottling techniques.