drag too low (in landing configuration?) & aileron ground trim

[Underbird]

Dear inibuilds team,

let me first of all thank you ever so much for bringing the Bf 108, an aircraft I loved so much in FSX, to MSFS! As soon as I found out, I bought it, and am over the moon to enjoy your quality work!

However, having just completed my "Rhine journey", one issue became apparent to me, which may correspond to the some landing issues other users mentioned on the thread in MSFS' official forum:

The drag of the aircraft is too low, especially in landing configuration. For example, I managed to land at Haamstede airfield after having closed the throttles above the mouth of the Haringsvliet (real weather) at an altitude of 1 km without opening the throttles ever again. This equates to a glide ratio of roughly 1:25, with the gear lowered and flaps set to 10° for the final third of my glide. Without having an official document to hand, and with great respect to Messerschmitt's creation, I still think this value is too high! Effectively, this makes it tremendously hard to slow the aircraft down to the approach speed mentioned in the checklist.

Best,

Underbird

 

PS:

I appreciate to see the aileron trim working in the sim, even though the real aircraft was not equipped with one (I believe). However, it seems it is set too far to the left by default, leading to a pronounced roll tendency on take-off, which can be solved by "guessing" and moving the aileron trim to the right before opening the throttles. Would I possible to look into the default setting of aileron trim, and set it to what could be considered ground trim, i. e. a setting to compensate the rolling tendency at cruise power and speed.

[Deleted Account]

Heya!

I just tested this. I spawned at 1.2km, 220kmph and I made from 13nm (about 25km) to about 6nm short of the runway. It might be a little higher than a standard GA aircraft, but consider a fighter of the time had a glide ratio of 13-14:1 I am not shocked by a 12km glide to give a 12ish:1 glide ratio.

Remember, idle thrust does not equal no thrust. Even if at idle, it will still generate thrust to move the plane forward. You'll have to turn the engine off completly and redo your test to get the actual glide ratio.

[Underbird]

Good morning gumbyger,

that's a fair point, and something which has to be taken into consideration. Nonetheless, as normal procedures do not require turning one's engine off for approach, I believe the current behaviour cannot be correct. 

A Grunau Baby, a period glider, had a glide ratio of 17!

Best,

Underbird

 

[Deleted Account]

I.. don't know what you want me to say. We do believe the current behavior is correct and within the expected values.

If you want to slow down quickly, get the plane to 185km/h and put flaps out. That's what the pilots told us how it was in the real thing as well

[Deleted Account]

To add to this, when you enter your circuit, go to idle throttle, maintain level through increasing AOA, the speed bleeds off quick enough to where you can introduce flaps / gear to get down to the runway.

I normally go to 20-30 degree of flaps and gear down during the downwind at around 130-140 km/h, then 30-40 on the base leg. Turning final you should be at around 110 km/h which should give you a good speed for landing. Progessively control your speed with V/S and only use power if you're going to run short.

[Underbird]

 

Good evening gumbyger,

thank you for your reply; I'll try with your approach. You may consider this threat closed (although I'd love to see the aileron trim set differently by default).

Best,

Underbird

[Shortways]

I am actually of the opion that the Drag-profile is incorrect, as well. Deceleration in level flight is slow. The original manual indeed states to fly final approach in idle power. (It does not say, don’t make your final approach too long or your engine will stall during a go around, but that’s another issue.)

However it also says that should you make a shallower power on approach, suddenly taking away the power will make the aircraft rapidly lose speed! But that’s not what happens.

Edited May 30, 2023 by Shortways