Live Dev Q&A Poll

I think Asobo may hold part of that blame in terms of poor execution and insufficient testing, but I don’t think they should take all the blame.

Jorg may be the captain in charge of MSFS, and work for Microsoft directly, but the captain of the plane doesn’t decide where it gets to go and what routes it takes. That’s the airline (Microsoft). Jorg’s job is to get the MSFS plane to where MS want it to go. He certainly has some leeway, but ultimately, the folks above him truly call the shots. And I think their priorities will often take precedent over what the folks at Asobo or even Jorg may want.

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Absolutely-the new format is more in-depth.

Yes, I liked the format.
BUT: The actual voting / snapshot system with only three categories (Bugs, Wishlist, VR) is really bad. Imho this is a sim that is heavily dependent on community events or just flying with friends. After I saw how much votes we actually got on a multiplayer-issue regarding the visibility of the event organizer I have no hopes to get some improvements regarding multiplayer before 2025.
Please add a few more categories like multiplayer, visuals, avionics, etc. I do not need any improvements regarding ground traffic, as long as I do not see my flight leader because there are more than 50 people in an event. If there were more categories I think there would be a much broader view on the things people want to see or have problems with. Otherwise this will be a community of commercial airline pilots in a year from now, with no one who will be setting up a GA-Plane event anymore…

  • mo
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Much better format, they also answered some questions in chat when they could, it was better balanced and informative.

I know my one opinion is just that - a singular opinion in a sea of thousands of others. I just finished the Q&A. The Q&A always make me feel better… Jorg is pure genius, he knows how to speak to the simmer and always makes us feel better. But I also know that “saying” something is going to get better doesn’t always translate into action. As we’ve discussed ad nauseum, the issue for me, is lots of hype or promises and not so much execution. I am glad to hear that Asobo/MS get this and that they even mentioned the word HOTFIX today… I think this is the right approach so that if a bug comes up from the latest update, we don’t have to wait an entire month to get it fixed.

@Jummivana - back to your original question above, I LOVE the new format. It had direction, it was focused, I loved the presentations, and even the time to get chat questions in the Q&A.

We EVEN got a response on Photogrammetry/LOD (hallelujah) - thank you for finally giving us a bit of hope on the photogrammetry and LOD issues. I sure do hope Bing will figure out a way to improve the consistency and allow those of us with PCs to have better LOD.

I have been somewhat critical on some of the lack of execution but today’s Q&A does give me some renewed hope. The announcements on Working Title being full-time on the sim? This is AMAZING. They’ve done more for this sim than almost anyone else (outside of FBW) and this is awesome news.

I think we do need to keep the voting system, but also keep this new format so that it remains structured and keeps everyone on task. Others have already mentioned above, but I turn off the chat on Twitch - it’s just nonsense and way too overwhelming.

I also greatly appreciated all three of the gentlemen speaking about the community’s frustrations with things being delayed, or not properly tested or implemented. As many have said, it’s the ambiguity in dev posts or patch notes that cause much more stress/confusion. Examples: If the weather can’t be truly improved upon until later, then say “Q4 2021” is the approximate timeline and I think that will quell some of the constant criticisms. I feel like developers and studios are getting more and more scared of mentioning real dates… we get things slip and can be postponed, but ambiguity is never the right answer.

I also appreciated Jorg’s comments on the feedback snapshot. I have been guilty of this – thinking Asobo is ignoring the top issues because the snapshot isn’t updated with specifics or doesn’t seem to change from week to week. I will try to be more patient with this, as I realize now that “under investigation” really does mean what it says.

Last but not least, thank you for also finally acknowledging/updating us on the mirrored liveries issue and the premium content being locked away from 3rd parties. I understand IP and legal are the issue to this, but I still don’t like that answer as I feel like those of us who spent premium money on the premium content are getting the crappy end of the deal. I do hope Asobo can focus more time/attention on the 787 and longitude and other airplane that haven’t been improved upon, really, except for a HUD change or something small.

Great work Asobo/MS. Appreciated today’s Q&A.

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Perhaps there should be an option for both.

Answer the top community questions AND guided questions, just half of each.

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I loved the new format, this Q&A session was full of important & useful information.
And its great to know that the devs are passionate of the sim world as much as we are and that’s awesome.

Another super important thing is the acknowledgment of the performance issues that currently are stopping me from flying and I hope it will be fixed soon.

Congratz on getting Working Title on board, without a doubt top brains are on this mission to produce the best simulator ever.

See you guys at the next Q&A stream.

In my opinion, the format was definitely an improvement. That’s why I voted yes.

For me (I can only hope if others share this opinion) I would like 3 more extensions to the format.

  • First of all (as mentioned by some of the above), it would be desirable to keep the voting process in place in order to ask the important questions that the community desires.
  • On the Q&A agenda, would it be possible to ask the questions in the order of the list? And if you want to skip a question. Then please go to the next one. So it would be immediately clear which questions are not addressed and we do not necessarily need to scroll up and down.
  • After the show it would be nice if a question / answer protocol would be published and maybe even if possible a short answer to the questions that were not asked in the show.

@Jummivana Any chance this can be brought to the attention of the developers? Maybe the issue is clear and it got lost in translation during the developer Q&A yesterday. The explanation of the devs for the missing propeller drag is somewhat true but I don’t think it describes the core problem.

Thanks!

Crash Course in Propeller Aerodynamics

Concerning the last Developer Q&A, I’m not entirely sure the developers understand the problem of “missing propeller drag” in the sim. Seb was talking about drag from internal engine components instead of aerodynamic propeller drag. In all fairness, the drag of internal engine components had an effect on propeller windmilling speed and therefore aerodynamic drag produced by the propeller. I’m not a developer to be clear but I doubt this is the real problem. Also it would not explain the lack of drag on turboprops in MSFS as the PT-6 for example is a free turbine engine and therefore not influenced by drag of the engine itself, sure it has some drag from the reduction gearbox and power turbine, but I don’t think this is the real problem.

Edit: after doing some testing it seems like there is propeller drag modelled on certain aircraft. The single engine piston aircraft I have tested seem fairly accurate, the Baron isn’t accurate at all, the landing gear on the Baron does not produce any noticeable drag & able to fly way below Vmca without departure from controlled flight. All three turbo-props have no propeller drag modelled at all. None of the MSFS aircraft have the ability to feather the propellers although on the Kingair and TBM the RPM does drop significantly when selecting feather (but with no change in aerodynamic drag). In short: multi-engine piston aircraft and all three turboprops are significantly flawed.

Definitions

First it is important to understand the following definitions when talking about propellers:

  • Blade / Pitch angle - This is the angle between the propeller plane of rotation and the chord line of the blade. On a fixed pitch propeller this angle is fixed, on a Constant Speed Propeller (CSP), this angle is adjusted to balance engine power and propeller power absorbed, controlling the propeller RPM.
  • Washout or twist - The blade angle on a propeller blade is not the same along the whole range of the propeller, as the propeller rotates, the root of the propeller has a lower tangential velocity when compared to the tip of the propeller (compare this with a baseball bat, the tip of the baseball bat has a higher velocity compared to the root). In order to have the same angle of attack on the whole propeller blade the blade angle on the tip is lower than on the root (twist or washout).
  • Windmilling - Is the condition describing the propeller rotating by the forward speed of the aircraft rather than by absorbing power by the engine. When a propeller is said to be windmilling, the propeller is driving the engine instead of the engine driving the propeller. Windmilling is caused by a negative angle of attack on the propeller blade, essentially producing negative thrust (drag). You can look at it as a thrust reverse without having a negative blade angle. The windmilling RPM of a propeller is depending on the drag from the engine (in that regard the devs. are right) and aircraft forward airspeed (TAS). Lower RPM = lower drag, higher RPM = higher drag.
  • Forces - There are a lot of forces acting on a propeller, we will be looking at Lift (thrust) and Drag, the rest of the forces are of importance when trying to understand constant speed propellers. Centrifugal Twisting Moment (CTM), Aerodynamic Twisting Moment (ATM), centrifugal (feathering) weights added to the proppeller, springs in the propeller hub etc. we will skip those for now.
  • Fine & Coarse Pitch - On a constant speed propeller the blade angle is variable, a small blade angle is called “fine pitch” while a large blade angle is called “coarse” pitch. The finest pitch possible is the low pitch stop in flight and reverse pitch on ground (if installed), the most coarse pitch is the feather position (if installed).

Basics Aerodynamics

A propeller is an aero foil and essentially behaves like a aircraft wing orientated in the vertical plane. The working principle of a propeller is the same as for a wing, the only difference is that the resultant force is acting mostly vertical on a wing and can be divided into a vertical component (lift) and a horizontal component opposing the direction of movement (Induced Drag), on a propeller this resultant is acting mostly horizontal and can be divided into a horizontal component (Thrust) and a vertical component (Drag).

Very important, this is not the drag we are talking about in regard to the missing aerodynamic drag from (windmilling) propellers!

The engine power has to overcome the drag produced by the propeller, if the two are in balance the propeller RPM is constant, if the engine is producing more power than the propeller is absorbing, the RPM increases, increasing the thrust (and drag) until the two forces are in balance again and vice versa when reducing power.

Regarding constant speed propellers, this becomes a little more complex as there is an extra variable introduced. The propeller blade angle is variable, a constant speed propeller is able to MAINTAIN a certain RPM with an increase or decrease in engine power by modifying the blade angle, therefore changing the power absorbed by the propeller (higher blade angle is more drag and vice versa). For example if engine power is increased, the propeller tends to speed up but the blade angle is then increased producing more thrust (and drag), the increase of power is absorbed by the propeller with no increase in RPM! There is a limit to this, when power is reduced far enough the propeller will eventually reach the minimum blade angle, if power is reduced further the RPM will drop, if power is reduced further then at some point the propeller will start to windmill and drive the engine instead.

Propeller Angle of Attack

The angle of attack on a propeller is based on two components, the tangential velocity of the propeller and the True Airspeed. The tangential velocity of the propeller is depending on the propeller RPM, higher RPM is higher velocity and vice versa. We can’t call it “RPM” because the RPM is the same for the entire propeller, whereas the tangential velocity is not, it is depending on the location of the propeller, the tip of the propeller having the highest tangential velocity and the root having the lowest (zero velocity). To keep it simple we will call this component RPM, but technically this isn’t correct. I hope the picture below also illustrates clearly how we are looking at the propeller cross section in further examples.

In the first example the aircraft is stationary (TAS = 0), the propeller has a high angle of attack (AOA = blade angle) creating high drag on the engine. If we now release the brakes and start rolling the TAS increases which reduces the angle of attack, the reduced angle of attack causes a reduction in drag. The engine is now producing more power than the propeller is absorbing and therefore the RPM increases. This increases the angle of attack again to bring it back in balance, this is the constant force balance in play during flight. It is also the reason why on a fixed pitch propeller (e.g. Cessna 172) the RPM increases with increasing airspeed for a given engine power setting and vice versa.

Windmilling

Now the core of the issue. What happens if the we reduce power all the way to idle in flight? If the engine is not producing any power why doesn’t the propeller (and therefore engine) stop rotating? As soon as the engine fails or power is reduced to idle, the RPM drops significantly as the propeller absorbs more power than the engine is producing, eventually the angle of attack on the propeller becomes negative and the forces acting on the propeller will basically flip. Positive thrust becomes negative thrust (THE DRAG WE ARE MISSING IN MSFS) and drag becomes the driving force, keeping the propeller and engine rotating. This drag is very significant in real life and cuts the glide ratio short by a significant amount, the deceleration in real life is therefore also significantly higher than in MSFS and it is possible to make steeper approaches without picking up speed.

Note that a windmilling propeller basically acts like a thrust reverser, but at a positive blade angle.

Single Engine versus Multi-engine

Without diving deep into the working principle of a Constant Speed Propeller, Propeller Governors etc. There is a noticeable difference between single engine and multi-engine aircraft. The principles are all the same independent if we are talking about single-engine, multi-engine, fixed pitch or constant speed propellers. Also on a constant speed propeller the engine will windmill, the reason is simple, a constant speed propeller (it is in the name) wants to maintain a constant propeller RPM. If an engine fails or power is reduced to idle the constant speed propeller will drive the propeller to the fine pitch stop and from there it will essentially behave like a fixed pitch propeller.

Belief it or not, windmilling on a single engine aircraft is actually beneficial. From an aerodynamic and glide range standpoint, windmilling obviously isn’t a great benefit. But only having one engine, the main priority should be to restart the engine, windmilling of the propeller keeps the engine turning and increases the possibility of restarting the engine in flight. This is the principle difference between single and multi-engine aircraft. On a multi-engine aircraft an engine failure will not only cause asymmetric thrust, on top of this the windmilling propeller will cause a load of drag. On a multi-engine aircraft the priority is therefore to reduce the drag, secure the engine and continue flight on the remaining engine.

Reducing the drag of the propeller and stopping the engine is done by “feathering” the propeller. The blade angle is increased to a near 90 degrees which results in zero resulting force on the propeller blade, the propeller stops rotating and drag from a windmilling propeller is canceled. Feathering can be accomplished manually or automatically by the aircraft (i.e. auto-feather). Nice detail, the propeller blade angle when feathered is not exactly 90 degrees (few degrees lower in fact), if the propeller blade angle would be increased to 90 degrees the propeller blade would start to act like a wing and will produce a slight lift force (and therefore drag), the angle of attack is therefore kept slightly negative.

This is exactly the next problem in MSFS, last time I checked propellers are not able to feather, neither does the propeller produce drag as we know so the propeller performance in MSFS is basically a feathered prop anyway. When propeller drag becomes implemented feathering would become very important. At this moment, accurate simulation of asymmetric thrust and drag on multi-engine aircraft is unavailable.

In all cases below, flight model set to MODERN, assistance set to HARD, community folder completely emptied, ISA conditions, no wind.

TBM 930

Maximum weight, 120 kts glide speed, flown with FLC on autopilot, prop first feathered and then windmilling. I cut the engine (by closing fuel selector) overhead an airport at 3000 ft, ISA, no wind, glided down to 0 feet, paused the sim, took the drone camera to check my location, looked it up on Bing maps and measured the distance.

Prop. Feathered:

Propeller speed = 260 RPM
Glide range: 17.5 km = 57400 ft
Glide ratio = 57400 / 3000 = 1:19,13

Prop. windmilling:

Propeller speed = 960 RPM
Glide range: 17.1 km = 56088 ft
Glide ratio = 56088 / 3000 = 1:18,70

My methods are a little bit mickey mouse and completely accurate, the autopilot started to level off slightly when doing the glide ratio test with feathered propeller because I put 0 ft in the altitude preselect so thats were the extra 400 m likely comes from. It is safe to assume that there is absolutely no drag modeled on the TBM…

Next test, FLC at 120kt in descend, measuring vertical speed:

Flight idle: -700 ft/min
Windmilling: -650 ft/min
Feathered: -700 ft/min
Full reverse: -900 ft/min

Conclusion, no windmilling drag at all. In all situations the vertical rate is fluctuating between 650 and 700 ft/min.

Beechcraft G36 Bonanza

Speed 110 kts at FLC, max. weight:

Power idle: -1100 ft/min
Engine off: -1300 ft/min (mixture cut-off)
Low RPM: -1100 ft/min (mixture cut-off and prop full back)

Below, same test as TBM, power cut at 3000 ft overhead an aerodrome. Mixture cut-off, prop in low RPM, 110 kts at full weight according to the POH it should result in a glide ratio of 1.7 nm per 1000 ft.

Glide range: 4.9 nm
Glide ratio: 4.9 / 3 = 1,64 nm per 1000 ft

Conclusion, the G36 is pretty accurate! Maybe the problem only concerns turboprops?

Beechcraft Baron

Speed 110 kts at FLC, max. weight:

Power idle: -1000 ft/min
Engines off: -1450 ft/min (mixtures cut-off)
Props feathered: -1450 ft/min

Conclusion, not sure if the increase in rate if descent is because of losing idle thrust or if it is because of propeller drag. The props don’t feather, absolutely no response to propeller lever (RPM stays the same when feathering). Interestingly I accidentally left the gear down during this test so I rerun the test with gear-up with same results! The landing gear on the Baron does not seem to create a noticeable increase in drag.

Beechcraft Baron - Vmca demonstration

Beechcraft Baron
One engine full power, the critical engine windmilling
Take-off flaps, gear-up
ISA conditions
Max. TOW, aft CG

Seems the aircraft stalls before losing control due to asymmetric thrust and drag. I haven’t flown the Baron myself but I have heard stories about how it is handling single engine go-arounds and I even know someone who died practising single-engine go-around on a Baron. Can anybody with experience on the Baron confirm whether this behaviour is correct? Is it still climbing this well on one engine with flaps at take-off at speeds way below Vyse?

By the way the rudder axis on my joystick is seriously borked so I’m lacking precise control over the rudder…

Edit: I noticed I shutdown the wrong engine, I had the right engine in my head as being critical, forgot that the aircraft I used to fly has counter rotating props, oops…

Second attempt: now with the critical engine failed, 50% payload, gear down for some extra drag, first one flaps take-off, second one flaps landing:

Beechcraft Kingair

The Beechcraft Kingair is an absolute joke. I have flown this aircraft in real life, I can see it is seriously flawed.

Max. take-off weight, speed 140 kts on autopilot using FLC:

Power idle: -300 ft/min
Full reverse: -1150 ft/min
Engines shutdown, props full forward: -850 ft/min
Props feathered: -850 ft/min

I didn’t note the RPMs, the RPM does drop significantly when selecting feather, but with no effect on the aircraft drag. The difference between flight idle and engines shutdown is likely not an increase in drag but rather a way too high flight idle power setting…

When shutting down the critical engine (windmilling) and adding full power on the life engine, the aircraft stalls way before running out of rudder to counter the asymmetric thrust and drag. Second try with flaps in landing position to lower the stall speed, able to fly just 77 kts with the joke full back, rudder full in just keeping the slip indicator centered, again no departure from controlled flight below Vmca.

Cessna Caravan

Max. take-off weight, 110 kts on FLC (no idea what best glide speed is, I just picked a speed).

Power idle: -650 ft/min
Full reverse: -1050 ft/min
Engine shutdown, prop full forward: -900 ft/min
Prop feathered: -900 ft/min

On the Cessna Caravan the prop RPM does not respond when selecting feather. RPM remains the same. Conclusion, the three turbo props seem to suffer the most from incorrect (completely missing) propeller drag.

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I voted “yes” for many of the reasons already mentioned.

A stream like this with well-prepared answers and videos is a good way to delve into some of the more technical issues, but of course it also means that not everything can be addressed.

What matters most to me is that we get confirmation each time that MS and Asobo are committed to continuous improvements in all areas and that they hear what we say. There’s just so much to do…

Hello everybody,

Unfortunately, this report (regardless of how extensive it is) has nothing to do with the main topic “Survey on the new format of Live Dev Q&A”.

Sorry! but I think it would have been better to have a separate thread here.

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It has its separate thread, but some extra attention on the topic would be nice.

There is no thread discussing yesterdays Q&A itself so I thought, I’ll post a copy of the original post here just in case.

It definitely felt more organised compared to the previous Q&As.

Due to timing (in another part of the world), I don’t think it’ll be possible for me to attend the Q&A live. If there was some part that allowed for questions outside of the topics for people who can’t stream live (in a fair manner, of course), that would be welcomed.

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I really liked the format and the videos that Seb used to illustrate his points. I was thinking that a video for each update showing the impact of the fixes would be a helpful thing. So here’s a before and after video of this change we made to how the rudder works (or whatever) so we can actually understand here what has been fixed. Separate to the Q&A though.

Also it was really interesting about auto rudder. I don’t have rudder pedals so had turned that on to make take off easier - but I didn’t realise it significantly impacted on the rudder control throughout the flight.

Like many have said the chat was a mess and so only pre submitted questions are the way to go I think

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agree, but please make him stop talking that much ! He´s stealing time for so many other important questions :rofl: :joy: :rofl:
Just kidding, he´s doing good

Man! You really went all in here :rofl:. Great effort :+1:. I’m learning new things every day here :crazy_face:

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I think the IVAO/VATSIM question wasnt understood.

The ask was to see the multiplayer names for other networks rather than only LIVE. I can see the names of live players but as soon as I connect to VATSIM the planes are added but the LABEL is not there. Its rather simple.

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Right – it seems simple enough, but even after all this time, it has not been addressed, or even considered to be an issue.

I was totally amazed at the look of puzzlement on Asobo’s faces, and the statement that this was the 1st they had heard of this…

The 1st time I went on Vatsim with MSFS, it was so obvious.
Other sims can see Vatsim Plane labels, its only MSFS that can’t

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