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XyZspineZyX
08-14-2003, 08:53 AM
I dont know if this is a bug or what but I find that with the patch, the engine revs stay high when you chop the throttle at speed and only drops after quite a long while in level flight or climb.

I appreciate the fact that the prop will "windmill" and keep the revs up for a while but the drag should slow the plane down much quicker. I fly fixed wing single engined airplanes myself and I know that with modern commercial planes, the plane is much more responsive to a reduction in power than what is moddelled in the patch.

The aerodynamics of the WW2 planes may have been a lot different and correctly depicted in the patch, I dont know. By the way, I find this is most pronounced with the P40 and LA5FN and hardly at all with the LW aircraft.

Does anyone else find this a bit disturbing?

Cheers

Redshift

XyZspineZyX
08-14-2003, 08:53 AM
I dont know if this is a bug or what but I find that with the patch, the engine revs stay high when you chop the throttle at speed and only drops after quite a long while in level flight or climb.

I appreciate the fact that the prop will "windmill" and keep the revs up for a while but the drag should slow the plane down much quicker. I fly fixed wing single engined airplanes myself and I know that with modern commercial planes, the plane is much more responsive to a reduction in power than what is moddelled in the patch.

The aerodynamics of the WW2 planes may have been a lot different and correctly depicted in the patch, I dont know. By the way, I find this is most pronounced with the P40 and LA5FN and hardly at all with the LW aircraft.

Does anyone else find this a bit disturbing?

Cheers

Redshift

XyZspineZyX
08-14-2003, 09:56 AM
Yes, yes, yes, I agree completly, and this has been the one great disapointment with the patch for me. I am suprised that this has not been brought up by anyone else already.

I too am a PPL of 20 plus years and was taken back by this lack of speed decay, post-patch. Once up to speed, in level flight, I can close the throttle (of any a/c) and the speed bleeds off so slowly and there is no change in the engine revs!! This has made landings a whole new ball game, whereby you now need to start your decent with the field out of visual range and at a glide angle of about 1/2 a degree! Even the deployment of flaps has very little effect on speed loss. This is in no way born out by my own experience of flight and my lifetime as an Aerospace Engineer. DRAG is the master when THRUST is lost. This one anomally has spoilt an otherwise near perfect flight sim and I hope that Oleg will take note and correct this in the next patch.

I'd never join a club that would have ME as a member!!.

XyZspineZyX
08-14-2003, 10:03 AM
Agreed. Elem, will you report this as well? I understand that there is some speciffic bug reporting procedure. I will find out what this is and report to Oleg.

Cheers

Redshift.

XyZspineZyX
08-14-2003, 10:07 AM
Agreed, I sometimes damage my flaps trying to slow down to land :-P Then I start doing rolls, and going up and down on the pitch trying to break, till I get to a reasonable speed or else I start gliding at 400+... If I had to do this in a real plane, lol...

XyZspineZyX
08-14-2003, 10:19 AM
I wouldn't call it a bug, more an inaccuracy, but I think it needs to be reported.

From the readme...

Bug Reporting enables you to get across information about irregularities, problems, bugs and other defects in FB version 1.1b directly to 1C:Maddox Games via e-mail (special mailbox il2beta@1c.ru is issued to collect your information). You can also use the Bug Report to give us feedback on certain issues.
Before sending us a report, please convert TGA files to JPG, and zip large files.

Bug report form
1. Version Number
2. Computer (complete info. including versions and type of video/sound drivers and type of online connection)
3. Bug/Defect Description (short, including description for each screenshot or track, if is)
4. Describe steps to reproduce the bug (detailed)
6. File Attachment (Screenshots, tracks or logfiles)


I'd never join a club that would have ME as a member!!.

XyZspineZyX
08-14-2003, 11:27 AM
I agree

RPM not down at 0% power... ¿?

Somebody listen noise of flaps in He-111?


I have Win XP SP1, sound Terratec DMX XFire 1024. Drivers 3057, DX90a.

XyZspineZyX
08-14-2003, 11:43 AM
I think when you are landing you need to set throttle to 0% but also need to set prop pitch to 0% in order to slow down.

Is result of different gestion of prop pitch.

XyZspineZyX
08-14-2003, 11:49 AM
StG111_Shang wrote:
-
-
- I think when you are landing you need to set
- throttle to 0% but also need to set prop pitch to 0%
- in order to slow down.
-
- Is result of different gestion of prop pitch.
-
My observations are with CEM off!

I'd never join a club that would have ME as a member!!.

XyZspineZyX
08-14-2003, 11:53 AM
hi,

I too experience that the airplane,for me the Bf-109,c,ant bleed of the speed accurate.It takes to long to slow down.But I like the patch!

XyZspineZyX
08-14-2003, 11:59 AM
"I think when you are landing you need to set
-- throttle to 0% but also need to set prop pitch to 0%
-- in order to slow down."

This should not be so. In real life, you set the pitch to fully fine - i.e. 100%, as the sim calls it - during your approach to land. If you think about it logically, it cannot be any other way because if you suddenly have to go around for some reason, at the very last moment, you have to have maximum thrust instantly and this you can only get with a fully fine pitch setting.

So if you have to set the pitch coarser during approach in order to slow down then there is something seriously wrong. I have only tested the patch in QMB without landing. Tonight I will have a look at how this affects landing approaches.

Redshift

XyZspineZyX
08-14-2003, 04:56 PM
I really wonder why none of the beta testers picked up on this since it seriously reduces the airplane from being flown properly.

Did none of the beta testers attempted to land these planes or what?

PS: I already send a bug report form to the mail address in the readme a few hours after I installed the patch last wednesday.

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XyZspineZyX
08-14-2003, 05:36 PM
I really don't this is a "bug" guys. All of these A/C are heavy and for the most part pretty darn slippery. This makes them hard to slow down. Why do you think the overhead with two 90 degree turns was and is still used by fighters today? People need to stop applying their general aviation "experince" to this game since I would say very few A/C come close to simulating how these (WWII fighters) A/C slow down. Form all the pilots who flew fighters in WWII or fly these fighters currently I think IL-2 models these aircraft as best as possible. Just my own opinion and I could be wrong.

P.S. I do fly commercially for a living (CMEL+SEL, IA, CFII)

XyZspineZyX
08-14-2003, 05:41 PM
Have the same problem butt german planes don't have that problem,strange???

XyZspineZyX
08-14-2003, 05:49 PM
... same problem here. The engine does not - or almost does not - respond to cutting the power. Bad. Should be taken care of by the devs. Otherwise the patch is OK, imho.

Harald, a.k.a. Odin914

XyZspineZyX
08-14-2003, 06:31 PM
Yep - I agree that it seems like the energy bleed on landing is too slow.

I use manual pitch almost all the time. Before the patch, I could set pitch to 100% and cut throttle while landing a Bf109 to slow the plane down quickly.

Now, the revs stay high and the engine sounds like you're still giving it gas. The 109 does not slow as before and only reduces speed after a long, level, powerless flight.

It's even worse for FWs.

Anecdotally, I've read that FW pilots were instructed that without power the plane slows quickly and sinks fast.

Also, when coming in hot in a FW before the patch, I could give the stick a hard jerk up, put it into a short stall and immediately lose 40-50kph after bringing the nose down (like in "Space Cowboys"). Now, that doesn't work at all; the FW won't stall easy with exaggerated elevator input in level flight.

XyZspineZyX
08-14-2003, 06:40 PM
FlyingFerris wrote:
- I really don't this is a "bug" guys. All of these
- A/C are heavy and for the most part pretty darn
- slippery. This makes them hard to slow down. Why
- do you think the overhead with two 90 degree turns
- was and is still used by fighters today? People
- need to stop applying their general aviation
- "experince" to this game since I would say very few
- A/C come close to simulating how these (WWII
- fighters) A/C slow down. Form all the pilots who
- flew fighters in WWII or fly these fighters
- currently I think IL-2 models these aircraft as best
- as possible. Just my own opinion and I could be
- wrong.
-
- P.S. I do fly commercially for a living (CMEL+SEL,
- IA, CFII)

The Hurricane was a heavy aircraft?
Since when?

Did you even read the posts or did you just hit reply and started typing?

The problem is that when you cut the throttle (So the fuel is cut towards the engine) the RPM does not drop and the plane does not slow down, the only way to reduce RPM is to reduce prop pitch to 0% and according to you this is normal?

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XyZspineZyX
08-14-2003, 08:16 PM
Interesting thread...

The idea of setting prop pitch to Fine to slow the aircraft down is a bit foreign to me. The idea being that on approach you want maximum available power at the ready in case of a go-around. The constant speed prop is an interesting animal and its been a while since I flew in one. The RPMS do not fluctuate that much above idle throttle settings. If I remember correctly one set manifold pressures for take off, climb, cruise, descent and pattern along with setting for final approach. I will now have to check this out in FB!!!

Why can't we just fly for fun!



Happy hunting and check six!

Tony Ascaso, RN

XyZspineZyX
08-14-2003, 08:29 PM
This isn't a bug. Most planes in FB have constant speed props. This means that the engine will try to keep the same RPM and only adjust the prop pitch according to your throttle setting. The throttle is not linked directly to the engine but to the propeller governer. The prop pitch is like gears in a car. In a car, you try to keep about the same RPM for all speeds. In first gear, you may be going 15 MPH at 6000 RPM but in 4th gear you can be going at 60 MPH also at 6000 RPM. The engine will still make the same amount of noise because it's the same RPM. Also, a 2000 HP engine 3 feet in front of you will be loud no matter what the throttle. /i/smilies/16x16_smiley-happy.gif


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"Though the course may change sometimes, rivers always reach the sea."

XyZspineZyX
08-14-2003, 08:39 PM
- The Hurricane was a heavy aircraft?
- Since when?
-
- Did you even read the posts or did you just hit
- reply and started typing?
-
- The problem is that when you cut the throttle (So
- the fuel is cut towards the engine) the RPM does not
- drop and the plane does not slow down, the only way
- to reduce RPM is to reduce prop pitch to 0% and
- according to you this is normal?

Actually yes I did read the post, and I was trying to pass along what really is normal for radial/big inline engines. When I'm flying my beech 18 and I pull back the throttle from 18" manifold to 10" the props actually speed up before it goes down to the RPM the prop was maintaining. Imagine that constant speed props remaining at a constant speeds. You don't need to reduce RPMs is my point, this is a Skyhawk pilots mentality, if you're running only 10" of manny even 5000 RPM, all you're doing is spinning a prop fast, you're not putting any power through the prop. Before you attack me maybe you should read what I'm saying with a clue and then respond. And yes 5000 lbs. with a realtivly slippery airframe is heavy and <shock and horror> takes time to slow down. Once agian I actually fly a warbird trainer so what would I know.

XyZspineZyX
08-14-2003, 11:12 PM
So basicly constant speed props can keep the engine running at max RPM without fuel, on the other hand you can reduce the RPM nearly to 0 by setting prop pitch to 0% while still flowing fuel to the engine at maximum input.

That doesn't sound logic in any way.

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XyZspineZyX
08-15-2003, 12:07 AM
Cappadocian_317 wrote:
- So basicly constant speed props can keep the engine
- running at max RPM without fuel, on the other hand
- you can reduce the RPM nearly to 0 by setting prop
- pitch to 0% while still flowing fuel to the engine
- at maximum input.
-
- That doesn't sound logic in any way.


First off, a throttle doesn't cut fuel to the engine. It regulates the air flow. And no, ferris is not implying what you are saying.

Basically what happens is, you have two types of idle RPM's. Static (i.e. idle RPM achieved while sitting on the ground doing a run up.) and airborne (i.e. idle RPM achieved when you're flying through the air.).

Example, doing a pre-takeoff ground run of an aircraft (just a generic example here), you will find that it idles around say 600 RPM. That same airplane will idle around 1500 RPM while you're coming in on decent to final approach or in level flight. As the speed drops off in level flight however, the idle RPM's will also decrease. (The same will be true for full-power RPM as well. Roughly 2200 and 2500 respectively.) Believe me, this happens. I experience this phenomenon

every

single

day.

And while these numbers are very generic, this occurs on every single different airplane type I've ever flown. Fixed pitch props or constant speed. From T-34's and B-25's to Cessna Skyhawks and Diamond Eclipses.

The simple matter is the prop and engine don't have to work as hard to pull an airplane through the air when its got momentum behind it let alone when gravity is working for it. Additionally, the propeller is operating in excess of 100% efficiency while on decent, so regardless of your manifold pressures it will continue to spin at a higher RPM than it did during the static run up.

I, for one, was totally happy to hear this when I loaded up the patch. About time someone modelled that.

So, to Oleg and Co. Nice work! It sounds great!

regards,
UN

XyZspineZyX
08-15-2003, 12:15 AM
No they can't, but you must relize that the prop systems we're talking about have incredible rotational inertia and aircraft recip engines have very low compression so they will stay at high RPM for a long time. For example an R-985 on a beech 18 takes about 30 seconds to stop running (spinning) after I pull the mixture levers back to cutoff. so 0% power isn't zero fuel, it just means back to flight idle, so between the engine still produce power, the airstream over the prop, and the fact most prop disks were several hundred pounds of spinnning alumminum (agian in most cases) props will stay at higher RPMs. By the way a higher RPM on the prop helps you slow down anyways, greater frontal area.

here are two great articles to further clarify.
http://www.avweb.com/news/columns/182081-1.html
http://www.avweb.com/news/columns/182082-1.html

XyZspineZyX
08-15-2003, 01:53 AM
'Greater frontal area' cool - never thought about that.

I always thought of it as in a car - the engine brake is most effective in the low gears. In casu: the best way to slow down is to have high idle RPMs.

In fact if you imagine yourself in a car - it all makes sense. What happens if you shift to lower gears and stop applying throttle ? The engine will start making more noise and your speed will drop !

I too was amazed at this new thing (although somewhat mystified - I know jack about engines) - and I am delighted that some real pilots testifies that it is working correct, and that it extends my meager understanding of what is going on...