Stall after take off

[5urvivalis7]

First post here, hello all!

Quick intro - I'm new to DCS/Sim and an VR exclusive pilot with little previous flying experience. I am just learning to take off/land/use rudder in turns.

The other day I took off, climbed to about 1k meters. After the initial climb I banked hard right to checkout the two factory chimneys that were poking out of the fog layer. To my horror just as I pointed the plane straight down the engine cut off, where upon I started to lower flaps and started looking for places to land the plane. I couldn't see the ground because of the fog, so it was ultimately a guess where to put down the plane but in the end I ended up on a grass field and survived the ordeal.

My question - why did the engine stall? Is there a way to analyze this type of situation? What is the correct emergency procedure? Do you keep the landing gear up and try to belly land? On a related note, I tried to put the wheel down but it was stuck. Probably related to the engine failure.

PS Attaching a photo of crash scene after I had climbed out the plane.

[GPatricks]

Wild guess but I think you kept it under full power the whole time and cooked the engine, doesn't take long at all. As for emergency landings, I always keep the gear up as it's hard enough to land a 109 with power, let alone in a near-stall attitude.

[razo+r]

Is the prop governor turned on? If not, that will be the issue (unless you want to control the prop pitch yourself on purpose) 

 

As for emergency, feather prop and find a suitable field to land on, with gear up being easier and safer. 

 

If you want to release gear without engine, pull gear emergency release handle. 

Edited November 6, 2021 by razo+r

[grafspee]

It is very odd for me because K-4 ind DCS has the most reliable engine across all modules, i had 0 engine fails across all the time i play DCS. 

[Hiob]

Random failures enabled in the ME?

[Baldrick33]

On 11/6/2021 at 2:18 PM, razo+r said:

Is the prop governor turned on? If not, that will be the issue (unless you want to control the prop pitch yourself on purpose)

 

I lost an engine soon after take off with a cold start and that was exactly the reason why.

[5urvivalis7]

On 11/6/2021 at 3:16 PM, GaryR said:

Wild guess but I think you kept it under full power the whole time and cooked the engine, doesn't take long at all. As for emergency landings, I always keep the gear up as it's hard enough to land a 109 with power, let alone in a near-stall attitude.

I kept it at 1.35 ATA as per training, so I doubt I cooked the engine. Good to know regarding keeping the gear up.

On 11/6/2021 at 3:18 PM, razo+r said:

Is the prop governor turned on? If not, that will be the issue (unless you want to control the prop pitch yourself on purpose) 

 

As for emergency, feather prop and find a suitable field to land on, with gear up being easier and safer. 

 

If you want to release gear without engine, pull gear emergency release handle. 

 

This was probably it since it was a mission from which I had to cold start the engine, but went ahead and took off. Thanks! I will try to reproduce this scenario (unrealistic, I know).

I suppose feathering the prop would be one reason to use the manual prop governor mode.

I wonder if such an engine stall happens mid flight there is a way to restart the engine?

[razo+r]

No, no way to restart a seized engine like this.

[grafspee]

54 minutes ago, razo+r said:

No, no way to restart a seized engine like this.

Exactly, if engine starve of fuel or ignition it will still keep spinning, if your speed is high enough if you cut fuel engine rpm will still remain high.

When prop stops, this mean that catastrophic failure happen, like seizured pistons or crank shaft, no way to recover from this. 

[5urvivalis7]

Yep, I was able to repeat, though it happened a bit longer after take off. Sure enough I had left the propeller governer was in the forward position.

I thought the propeller governor merely adjusted the propeller blade angles. If this is so how can it cause the engine to seize?

[Art-J]

If you have the governor turned off, then it doesn't adjust anything, resulting in fixed pitch prop which can be overspeeded and kill the engine (unless you react yourself and load the prop manually using switch on the throttle).

Unlike in Il-2GB series, 109 in DCS always spawns in the cold&dark missions with the prop in manual mode (governor OFF). 

Edited November 10, 2021 by Art-J

[grafspee]

1 hour ago, 5urvivalis7 said:

I thought the propeller governor merely adjusted the propeller blade angles. If this is so how can it cause the engine to seize?

 

Prop governor adjust blade angles a lot, example blade angle range in P-51 is 23-65 degrees.

How it can cause engine to seize, easy when pitch is static engine rpm will go up when airspeed increasing. I assume that you don't observe your gauges, if you would, you would know that engine rpm were above red line, which is 2800rpm when you pass 3000rpm engine dies.

Reason why your engine didn't seize after take off is that you enter climb and kept speed low, once you leveled out speed increased and engine rpm with it as well, then booom

Edited November 10, 2021 by grafspee

[ZnarF]

As said Grafspee, I'm almost sure your engine failure comes from manual prop pitch - In the 109, always check on earth that if you change throttle, the "clock" indicating prop pitch automoves - if not, that indicates you're still on manual and should click the switch! Otherwise, the 109 is really stable and fiable.

[Reflected]

Taxi and take off with the governor set to manual at 12:00, take off at 1.3 ATA, and immediately after lifting off, set it to auto.

[razo+r]

Or even easier, set it to auto from the beginning and save some switch clicking during a rather busy phase of flight. 

[Reflected]

16 hours ago, razo+r said:

Or even easier, set it to auto from the beginning and save some switch clicking during a rather busy phase of flight. 

 

That's not a good idea for the takeoff run. Easier to control the torque with it set to auto - that's why it's stated in the pilots' notes too.

[razo+r]

It might not be a good idea but once you try it, you'll see minimal difference at the cost of no risk of blowing your engine. For me personally worth it. 

[Krez]

Gently apply throttle until you get to about 1.2 ATA.
Gently use toe brakes stay straight.
Use rudder once you get fast enough.
Gently push forward on the stick until the tail comes up.
If you can't maintain a straight line going down the runway, practice that until you can.
The 109 will lift itself into flight without you having to pull back on the stick.
She will try to roll as soon as you get airborne. Counter it but gently.

The biggest issue with taking off in the 109 is the pilot's tendency to overcompensate.

FYI, I use full nose down trim, no flaps, and governor set to on.


 

[5urvivalis7]

2 questions:

The training module tells me that I should use full right rudder even before the plane starts to move to compensate. I see videos on YT where people just use right stick movement to compensate. I tried to just use the right rudder and it was harder. Is there a "right way"? BTW I discovered the other day that take off assist was set to 100%.. just when I thought I was getting the hang of it! DOH!!!

2nd question is - when do you actually use the propeller governor?

[Art-J]

All warbirds in DCS have takeoff assist turned on when freshly installed or when you reset game options. Something to remember for the future.

You probably struggled with rudder because you and computer assist were trying to use it at the same time and that's just recipe for trouble.

About the quesions:

1) You can't negate yaw on takeoff with ailerons (especially early on when there's insufficient airflow for them to do anything) - they do help with a bit of ROLL tendency just before liftoff, so a bit of right stick might help indeed. For the YAW, however, it's all about the rudder. It works in propwash all the time, so full right is OK initially, even if it doesn't seem to be enough for the first 4-5 seconds. It will gradually become more and more efective once the airplane picks up speed and you will see when to start neutralizing it.

2) you mean "auto" mode? For novice users - all the time - that's what it was invented for, to relieve pilot from tinkering with yet another control when they're already busy with all the others. That being said, it is profitable to switch it to "manual" in some circumstances. As mentioned previously, it can be used for takeoffs as well (reduces the left yaw tendency a little), but don't forget to switch it to "auto" after liftoff, otherwise you'll overrev and kill the engine again.

 

Edited November 19, 2021 by Art-J

[grafspee]

I would recommend using manual mode, just before take off you set pitch for  12 o'clock (there is a gauge in right hand side of the cockpit similar to the watch without numbers) assigning buttons for this will make it easier for use.

Take note that manual prop mode is intended for low power take offs, i mean you can do 1.45 ATA but engine will over rev very quickly after lift off and switching to auto would be necessary right after take off.

You can use auto mode for take off but this makes things harder to control because when you moving throttle you are changing target rpm for prop governor, the safe way of doing take off with governor in AUTO is to hold brakes run up engine to what ever power you need it could be 1.2ATA or 1.3ATA then release brakes and you don't touch throttle, this way will provide you with steady engine rpm during take off, makes thing easier.

K-4 is very specific in rudder use, because you will need a lot of rudder input in 2 phases of take off, first is initial roll and second is while tail rising up this swings K-4 to the left quite hard to negate it you will need to apply right aileron and a little bit back pressure on the stick this will slow down tail rise rate.

Edited November 19, 2021 by grafspee

[Sprool]

I've come across a few people saying thees a bug with the fuel pump sliders which causes the engine to overheat and seize 20 secs or so after takeoff - this is regardless of govener setting.

 

[razo+r]

4 minutes ago, Sprool said:

I've come across a few people saying thees a bug with the fuel pump sliders which causes the engine to overheat and seize 20 secs or so after takeoff - this is regardless of govener setting.

 

Get a track from them and post them here. 

[Art-J]

1 hour ago, Sprool said:

I've come across a few people saying thees a bug with the fuel pump sliders which causes the engine to overheat and seize 20 secs or so after takeoff - this is regardless of govener setting.

 

That used to be the case after pumps lever was changed in the game from key-operated to axis-operated and the pumps used to switch off when the lever was moved full forward (hence the engine cut off, not the overheat). I'm not affected, 'cause I use a mod which reverts to previous operation, but that problem occured many, many, many versions ago and I could've sworn it was fixed already last year. How old are these posts you've came across?

[Sprool]

about 18 months - one of them was a start/taxi/takeoff tutorial from Reflected, he mentioned the fuel pump slider and no im not asking him for a track file