OB 2.5.3 FM Change?

[Nealius]

I just updated to 2.5.3 on the Open Beta today and took the Yak for a spin. It seems like the FM has changed a tad but I didn't see it mentioned in the notes. The two main things I noticed are that I need right rudder in straight-and-level flight (I needed left rudder prior to the patch) and acceleration is slower in a shallow dive than it used to be.

 

The latter is IIRC more realistic according to one of the Yak pilots on here, but what's with the switch in the rudder?

[bbrz]

Maybe the ground adjustable rudder trim has been implemented?

[Nealius]

Is that a new trim control or a new option in the Specials tab?

 

I also noticed the pitch-up moment when deploying flaps seems a lot tamer than it used to be.

[bbrz]

It's the tab in the specials (where it definitely doesn't belong. Should be in the mission planner)

Just tested and it still doesn't work. :(

Less flap pitch change is confirmed but the flaps are still as draggy as before.

[gulredrel]

I think there were different changes in the latest update.

For me. the Yak seems far better now. Governing range of the propeller in connection to speed and manifold pressure has been improved a lot and seems more logical and corresponds to what I'm used to other sims radial engine behaviour. The same goes for improved coolant behaviour (cyl. head and oil temp).

 

 

Thanks for the recent update :thumbup:

[bbrz]

Governing range of the propeller in connection to speed and manifold pressure has been improved a lot and seems more logical and corresponds to what I'm used to other sims radial engine behaviour.

Interesting, just tested an got basically the same wrong RPM/MP relationship as before, but the prop seems to respond much faster now to prop lever movement.

本帖最后于2018年8月30日，由bbrz编辑

[gulredrel]

[...] got basically the same wrong RPM/MP relationship as before [...]

 

 

Which exactly?

[bbrz]

https://forums.eagle.ru/showpost.php?p=3599163&postcount=4

[gulredrel]

Okay, I see.

But it definitely changed in the current 2.5.3 open beta.

 

 

Before you could not cruise 65% rpm and 600 to 700 mmHG of MP. Adding MP resulted in rpm going above 70%, so as the governing range was reached. This works now. Can't tell for sure for the complete speed, rpm, MP settings combinations, but it's definitely more reasonable in 2.5.3 OB.

[Nealius]

Deceleration also seems rather difficult now. At 82% RPM and 4 boost, I cruise at 180kph. Getting slow enough to deploy gear requires a total throttle cut.

[jcdenton]

What are good settings for aerobatics? I've been using 90% RPM, 7.5 [units of pressure] at 2000', both cooling things fully open, and maximum pressure and minimum temperature in the mission editor. Each flight lasts ~16 minutes before the engine quits (not seizes), but I got up to 25 minutes just by lowering the RPM and not the power setting.

 

I guess what I'm asking is, what's an intuitive relationship between RPM, performance, and engine longevity? In the Bf 109 module, low RPMs are much worse for the engine but the same approach (max RPM, manifold pressure below some threshold) doesn't seem to apply to this engine, whether due to general design (inline, radial, air-cooled vs. water cooling) or whatever.

本帖最后于2018年9月1日，由jcdenton编辑

[AcroGimp]

Max continuous power is 82% RPM and essentially any MP up to 800 mmHg.

 

The actual M-14P is an extremely reliable engine that is tolerant of anything other than severe overtemps.

 

'Gimp (DISCO vVMFA-122)

[Dwarf_Hunter]

Max continuous power is 82% RPM and essentially any MP up to 800 mmHg.

 

The actual M-14P is an extremely reliable engine that is tolerant of anything other than severe overtemps.

 

'Gimp (DISCO vVMFA-122)

 

Hi, What can you tell us regarding the DCS FM in respect to the real deal?

[jcdenton]

Hi, What can you tell us regarding the DCS FM in respect to the real deal?

 

That's sort of a general question. Did you see this thread already?

 

One change I noticed with this update is that it takes less forward trim to fly inverted, although it's a slight enough difference that I could be imagining it. The inverted fuel tank is still not modeled.

[lobo]

The inverted fuel tank is still not modeled.

 

Curious why you say this? I can fly inverted for the limit of 2 minutes with no problems.

[bbrz]

I can fly inverted for the limit of 2 minutes with no problems.

Confirmed. I didn't try for the whole 2min, but the engine continues to run smoothly during inverted flight and negative acceleration.

[Philipp2]

I dont know why, but the Yak isn't maneuverable as she should be. Especially the aerobatic maneuvers with a high part of engine torque and snaps will need some redo..

 

 

 

 

There you can see a huge difference..

[lobo]

Airfield Alt? Fuel load? OAT? Apples to apples?

 

I dont know why, but the Yak isn't maneuverable as she should be. Especially the aerobatic maneuvers with a high part of engine torque and snaps will need some redo..

 

 

 

 

There you can see a huge difference..

[Hoffster]

Maby the one in video is equipped with M14PF and 3 bladed prop as well.

[AcroGimp]

The current Yak flight model, in my opinion as a Yak Owner/Pilot, while improving is actually still 'too' maneuverable, stick and especially rudder forces are way too light and it still lacks sufficient negative elevator to reliably effect any of the outside maneuvers see in the linked video (still cannot get a clean outside snap or any kind of inverted spin entry as of my last attempts Wednesday evening).

 

I have finally been able to get a vertical Lomcevak using the proper technique but understand that is with a slow deliberate movement of the stick and it is not what I consider repeatable yet.

 

IRL most (but not all) Yak's with the 3-blade prop (clearly seen in the video) are running with hopped up engines of 400-420 hp, or more - lots of mods from increased compression pistons to using the -PF supercharger gear set, etc.

 

ED is making progress but there are still substantial variations from the real aircraft.

 

The engine should not hesitate, stumble or hiccup at all under negative G.

 

'Gimp (DISCO vVMFA-122)

[IvanK]

"The engine should not hesitate, stumble or hiccup at all under negative G."

Fixed in Dev version

[Philipp2]

 

 

another good example ... Looks like a normal 2 blade and standard engine ;)

[bbrz]

"The engine should not hesitate, stumble or hiccup at all under negative G."

Fixed in Dev version

? This has been fixed already in the open beta since approximately 2 weeks ago. See post #16 in this thread.

[Hoffster]

With todays big update i wonder what we got for the yak. Besides the incomplete update log stuff. I have not had time to test yet.

[bbrz]

Didn't notice any improvement. MAP gauge, flap drag, rudder and aileron trim, everything wrong/inop as before. A bit frustrating since this a non FBW, no ADC etc. equipped, rather basic, airplane.