Originally posted by Knegel
To show the strange dragload setting of the La7 in AH you also can make deceleration tests. Use a 190D9, a 109K4 and a La7, accelerate at sea level to around 350mph, push X (autoleveler) and cut down the throttle to zero. Take a stopclock and count the time from 300mph to 200mph.
As result i get the K4 as fastest decelerating plane(around 17,5sec), then the 190D9 with around 18,5sec and then the La7 with around 19sec.
Looks like the 1000kg and the resulting inertia, which limit the climb of the 190´s so much, dont count while decelerating. The 109K had next to the more streamlined engine also a smaler wingarea, therfor i guess its drag wasnt more big than that of the La7, while it had more weight, so the faster deceleration looks strange too.
I have some sympathy with this claim but admit to not knowiing how great the effect is upon the "trueness" of the model.
Timing deceleration in level flight presumably factors in both lift related drag as well as pure drag. Albeit that showing the time for a higher speed will increase the pure drag effect.
Would another test be to take the ac to 10k set the auto speed to 350 (or what ever the max is)then switch off the engine and time the descent between say 5000 and 0?
Then we have a high constant speed dive test that emphasises the effect of pure drag and minimises the effect of induced drag. The higher drag should hit the ground quickest .
Hence an La5FN should hit the ground quicker than an La7 (it has a poorer pure drag coefficient)
109's should all hit pretty much the same time as each other with the heavier and less slip streamed later models hitting just ahead of the earlier models.
Based upon Tsagi/VVS trials I have the La7 should hit the ground before the 109G2.
I have never noted any comment from HTC re how drag is modelled..............and indeed this might rightly be treated as a confidential matter by HTC.
knegel rightly states that there is a large grey area open for opinion about the RL actuality.
I struggle with understanding of Knegels ebleed arguements during manouvering..............main
ly because I dont understand.
I look upon the balance as being
Kinetic Energy =thrust + (mass* accel) - total drag
In manouvre I believe total drag is predominently induced drag and this is a function of G incurred which as we know also carries a large mass*accel component along with some sort of efficiency factor for the wing profile.
Also in manouvre thrust is "out of plain" such that eventually the thrust vector is displaced and the total drag increased to a point where the manouver cannot be sustained.
We have curves/diagrams that show this. I would comment that most folk who test AH's curves in this respect with RL curves seem to think that AH models stuff very near to actuality........... better in fact that most other sims.
Of course there are no such RL curves for Yaks or Lavochkins! or at least I have never seen one.
What we do know about these ac is
Various max speeds, climb rates, sustained turn times at speeds/angles, roll rates, weights, wing loadings, wing profiles, generic dimensions, engine power and prop dimensions.
Even given all this I would expect a model to have to have some gaps filled in re drag and wing efficiencies.................
. but then what do I know?
