Actually if you slow down from v2 to v1 then the change in kinetic energy is
deltaE = 1/2 m (v2² - v1²) not 1/2 m (v2-v1)². So if v2 = 150 kts and v1 = 145 kts, then the change in kinetic energy is 585 kJ, so quite a bit more.
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Exactly my thought 
I remember something like this…
Windmilling: quite a bit of drag
Feathered: significantly less drag.
In a few light twins this could be the difference between being able to maintain altitude on one engine or not.
Sure a well lubed engine will reach a higher prop rpm when windmilling compared to a rusty old engine at a given airspeed during unpowered flight, due to said engine friction.
But will the windmilling prop slow the plane down enough? By 10-15 knots, or just 5 knots? That´s the type of parasitic drag I believe we’re discussing.
Giving the engine more friction might not slow the plane down enough, just give us a lower RPM.
Again, not a lot experience of flying planes since I’m a rotorhead, but have seen similar dilemmas regarding autorotation-rpm / descent-rate with different pitch settings / airspeeds.
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Your choice of words are unfortunate.
None of us are disputing that Asobo is modelling some form of propeller drag. However, as pilots we are not encountering ANY indication that the drag of the propeller itself is being modelled. The fact that there is no significant yaw imparted when pulling the power off on one engine while flying a twin is proof of that.
Hop into the Baron. Take off and pitch to 80 knots (at full throttle and RPM to 2600), just below that little blue line. At 200 ft AGL reach over and pull the mixture for the left engine all the way back. If you don’t crash, Asobo didn’t get the propeller drag modelled correctly.
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I have no idea how advanced their propeller drag modelling is, I’m not a developer. I can only compare MSFS to real life experience and I don’t feel like there is any propeller drag modelled. I assume we can find it out for sure using developer mode, there probably is a debug function somewhere there.
It was great, thundering down the ILS in the Dash 8-100 at idle, 900RPM and high speed.
Quickly shove the props forward to max (1212) RPM and you were really hanging in your shoulder straps.
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Not entirely fair, the PC-6 is able to go into beta in flight 
…
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If you really go into beta on the PC-6, the POH limitation applies:
Vertical descents are prohibited 
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By the way guys, we landed today with 25 kts crosswind gusting 35, I kept an eye on the FMS wind read out and in the flare it was still 25 kts. So this thing MSFS is doing with reducing the wind speed by half on the ground is bogus…
I will check it a couple of more times next week.
I think @hobanagerik brought this up a few days ago.
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The ATR is a bit more “slippery”. Although the Dash is a little heavier than the 72, the engines and props are way bigger, the ATR is a little underpowered. If I remember correctly the RTO is 2750 SHP per engine.
There is this rule of thumb on the ATR to start deceleration at indicated airspeed x 10. So 250 kts x 10 = 2500 ft. That way you’ll be stabilised at 500 ft AAL. On the 72 it never worked though, its always too late, I’m not sure if it works on the 42.
For anyone in doubt about propeller drag, and how significant the drag is in real life, especially during an engine failure, those things can be big:
Interesting - I certainly agree that at a medium/large municipal/international airport which is wide open and there aren’t trees screening the runway close by then the wind shouldn’t drop off much at the surface. I guess however with a small GA plane landing at a tight local airport w/ lots of trees and/or buildings/hangers nearby the wind should drop off a good bit close to the runway. I guess this is one of those small details that eventually hopefully can get hammered out and that depend on the situation (all adding to the complexity of course).
Probably, but having the wind / 2 everywhere does not make sense. By the way wind is measured 10 m above the runway surface in aviation which might be above part of the trees but /2 is excessive I would say. Also this was at a small regional airport, not as tightly locked in with trees as some small GA airports maybe.
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Definetely right Sir! It’s one of the reliable test-check to make in order to have an idea if the propeller drag is modelled in a realistic way or not. I’m still surprised that it seems to not affect the wish-list on a the top as it should be for the sake of realism!
Can you imagine what’s going to happen if you are experiencing a reduction gear failure with these props on takeoff?
We had this (luckily) on the Dash7. No feathering, nothing. Lots of sparks flying out of the nacelle and the prop immediately froze.
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This is what will happen:
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And the prize for most bizarre thread with over 800 posts goes to…
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I think this sim is great but I get the impression that few if any people in Asobo are pilots. They may have flown sims but haven’t been through the basic training that a pilot does and therefore don’t even have the BASIC knowledge that any PPL has and is tested on. I seem to recall (years ago - pre youtube) that in the days of FS7/8/9 there was an article on the then FS studio and half the developers were PPL’s or training to be one. That’s maybe why there are unusual characteristics with flight models. Having said that I had a few circuits of Newquay/St Mawgan tonight with Tommy’s DA62 and Rex inputting weather - big crosswind s etc and I had a sweat on - quite challenging! Seemed quite realistic to me, without the seat of the pants stuff. Never flown a twin IRL just Pa28’s/C172’s and not for a few years. Keep Flying and keep happy guys!
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There is at least one if Seb is to be believed in the Q&A - he often references his real life flying
Sure, I haven’t listened to that but there are one or two “interesting” takes on the flight modelS so…! Having said that, all previous versions of MSFS (from FS5 but NOT FS10) the default aircraft have been awful just awful (let alone scenery!) so i@m not entirely sure why people are expecting an exceptionally accurate flight model/avionics etc this time. MSFS has always provided the basis for the independent developers to do their thing.
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