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Issues starting aircraft


crudboy12

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Lately, when I try to start the Huey, I cannot get the aircraft to start with the throttle at the low setting, I have to move it quite a bit up before the engine will start, at which point the engine starts with a three foot orange flame coming out of the exhaust. I used to be able to start it normally, what gives?

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A-10C, FC3, P-51, BF-109, UH-1, MI-8, KA-50, M2000C, AJS-37, Gazelle, F-5E, L-39, F-86, MiG-15, MiG-21.

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I wouldn't worry about the flame, it's just a visual effect. (Actually, flames are normal when starting some engines)

 

Watch the EGT gauge and make sure it doesn't go over the redline.

DCS modules are built up to a spec, not down to a schedule.

 

In order to utilize a system to your advantage, you must know how it works.

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  • 4 months later...

As standard procedure you have to place throttle to iddle for startup. Also "decrease" 10 seconds the linear actuator (drop compensation system).

 

That will avoid flames in startup that is a matter for an emergency procedure to be applied and a maintenance inspection to be conducted.

 

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In 1.5.7 cold start procedure appears to be broken. Same cold start procedure works fine in 2.1.1.

I think there is a bug with fuel flow or fuel gage, as fuel gage shows zero fuel during start-up.

 

In order to have proper indication at the fuel gauge, you need AC. And you have no AC till you switch on the Main or the Aux Inverter, that is usually after reaching idle RPM, unless you are using external power unit and switch on the inverter before hitting the start button.


Edited by McFlurry
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Quite right. Still the cold start at start in 1.5.7 is broken, at least for me. The turbine does not turn. In 2.1.1 cold start works just fine. In 1.5.7 if the mission is started hot with turbine turning, then shut down, allowed to cool, the cold start procedure works. But not at start of mission. I thought maybe I was mishandling throttle Stop switch, but that is not it.

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You can check that. However I discovered that in that mission, if UH-1 has external power , it starts up fine , per normal cold start procedure. Why on this mission, I cannot say.

 

I think, but not sure, that DCS UH-1 cold start deviates from real world, turbine start up, is that throttle is not advanced to idle, until there is 10% engine RPM(from starter or ext power). Then throttle is opened and advanced to idle to spray fuel into turbine. The TOT should be between 100 and 150. Once startup is started, DO NOT stop the process , in RW, that could cause either starter generator or turbine to overtemp, and OT lamp to light.

I tried this in DCS and it also works fine, but throttle has to be opened at 5%. Without throttle at idle, turbine RPM will not ago above 5%. Also in DCS , as in RW, the starter generator clonks out at 40 seconds. Without ext power , there is enough battery for two attempts.

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I have not flown the Huey in 1.5.7 yet, but in 1.5.6 I had problems to start it again after engine shutdown. Cold start from ramp was not an issue, but if I shut the engine down after flying and then tried to start it again after some time it always refused to start. It felt like the battery was empty, but it was almost full. So there might indeed be something fishy here.

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DCS Panavia Tornado (IDS) really needs to be a thing!

 

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Ok. Here it is what I have found.

 

OAT is -18ºC. With that temperature you must expect a high battery energy drop, even if initial reading looks ok.

 

That is what happened. As soon as you hit the start button, DC VOLT drops below 14V and keeps droping, being unable to complete the engine start-up. In the image, reading is at 8 volts after a few seconds of the star-up try. That is quite normal at such low temperatures.

 

qEvtP7w.jpg

 

 

 

Instead of using the battery you must request the external power unit to avoid DCV droppage, as you have already found.

 

YXeh0yV.jpg

 

Then the start-up runs quick and smooth. Remember that this is normal at such temperature range. It is also good not to switch on any additional equipment, till the GENERATOR lights comes off.

 

Real life procedure for de UH-1H is to set the throlle slighly below the iddle position, better to say the iddle detention position (1/8 turn is enough). That's just in case you have to close the throttle in a hot start/engine fire situation, you don't have any problem to close it. Decrease ten seconds, fuel pump on, and hit the start trigger till 40% a maximum of forty seconds.

 

You don't press the start trigger and then move the throttle when N1 reaches a due percentage, as you do, for instance, with the UH-1N (Bell 212).

 

With regard to second and following starts after flying. First, keep an eye on the EGT. It's advidsory to have it below 100ºC if possible or pay great attention to a sudden EGT rise during start-up. And second, battery may not have recovered from the first start of the day, specially if it was a "hard" one. Maybe it is a little bit to much overdone in the sim.

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It felt like the battery was empty, but it was almost full.

 

Keep an eye on DC VOLT indicator while starting. It may drop below 14ºC initially, but it has to recover above that when N1 reaches 10%. At very low temperatures or with an exhausted battery it may fail to recover.

 

If battery initial reading is below 24V, you better use APU if available.


Edited by McFlurry
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Keep an eye on DC VOLT indicator while starting. It may drop below 14ºC initially, but it has to recover above that when N1 reaches 10%. At very low temperatures or with an exhausted battery it may fail to recover.

 

If battery initial reading is below 24ºC, you better use APU if available.

 

°C? I think you mean V ;)

 

It happened to me several times now when flying on the BlueFlag server. I flew quite some time (usally between 15-30 minutes) to my objective, land somewhere close to it and shut down to wait for friendly forces to clear the objective. When that happened I wanted to spool up again to move in the objective, but that doesn't work. The temperature there is around 20°C I think, so that can't really be an issue and I did check the volt indicator which, set to battery indication, showed 20-25V when I tried to start up again. :dunno:


Edited by QuiGon

Intel i7-12700K @ 8x5GHz+4x3.8GHz + 32 GB DDR5 RAM + Nvidia Geforce RTX 2080 (8 GB VRAM) + M.2 SSD + Windows 10 64Bit

 

DCS Panavia Tornado (IDS) really needs to be a thing!

 

Tornado3 small.jpg

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°C? I think you mean V ;)

 

It happened to me several times now when flying on the BlueFlag server. I flew quite some time (usally between 15-30 minutes) to my objective, land somewhere close to it and shut down to wait for friendly forces to clear the objective. When that happened I wanted to spool up again to move in the objective, but that doesn't work. The temperature there is around 20°C I think, so that can't really be an issue and I did check the volt indicator which, set to battery indication, showed 20-25V when I tried to start up again. :dunno:

 

Yes, you're right. 24V :D

 

Below 24V, can be bad news.

 

Instead of shutting down de huey, try to keep it at 5.500 rpm (all pumps and pressure levels ok).

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Yes, you're right. 24V :D

 

Below 24V, can be bad news.

 

Instead of shutting down de huey, try to keep it at 5.500 rpm (all pumps and pressure levels ok).

 

That's not a good solution for various reasons:

- It makes it easier for the enemy to spot me.

- It's loud so I can't use my ears to listen for enemy jets and combat

- It consumes fuel

 

I honestly can't believe that it shoudn't be possible to shut down in the field and spool up again later :huh:


Edited by QuiGon

Intel i7-12700K @ 8x5GHz+4x3.8GHz + 32 GB DDR5 RAM + Nvidia Geforce RTX 2080 (8 GB VRAM) + M.2 SSD + Windows 10 64Bit

 

DCS Panavia Tornado (IDS) really needs to be a thing!

 

Tornado3 small.jpg

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That's not a good solution for various reasons:

- It makes it easier for the enemy to spot me.

- It's loud so I can#t use my ears to listen for enemy jets and combat

- It consumes fuel

 

I honestly can't believe that it shoudn't be possible to shut down in the field and spool up again later :huh:

 

OK, whatever fits your needs. That is a common procedure for being on hold in some tactic situations but you are right, it has some possible disadvantages.

 

With a good and healthy battery there should be no problem to start-up again in the field. Sometines, the Crew Chief brings an spare battery to the missions, just in case something similar happens.

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The outside temperature was low. You live you learn. Prior to this mission, I have never requested ext. power for UH-1. For MIG21 , yes. I also noticed that with ext power start up was almost 2X faster. The RPM on turbine went to 40% in 25 seconds, while with battery and starter gen , it takes around 35-40 secs.

Anyhow, thank you for clarifying it.

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