correct as-is The Aircraft will not start.

[Guest]

After todays OB update the F-16 will not start manually or with auto. The rpm goes up to 24% and stays there like it will not register that you put the throttle to idle position.  

[BIGNEWY]

Hi,

 

please ensure the RPM has stabilized at 20% before enabling the JFS

 

Thanks

[Guest]

Weird, i had to restart DCS for it to work.

[Northstar98]

On 9/17/2021 at 7:39 PM, BIGNEWY said:

Hi,

 

please ensure the RPM has stabilized at 20% before enabling the JFS

 

Thanks

 

Do you mean before advancing the throttle to idle? As you need to use the JFS to get the engine to 20% in the first place.

 

To the OP: after enabling the JFS you need to watch your RPM guage, it should advance to 20% and the SEC caution light should extinguish, the RPM should continue climbing and stabilise at around 25%, once it's stabilised at around 25% RPM is when you move the throttle from off to idle.

Edited September 20, 2021 by Northstar98

[spidierox]

Had the same issue. Also it seems after quitting DCS and coming back in the same mission I could start it.
Anyway have to look into the procedure as mentioned by the poster here above to be sure.

[JeffreyC]

Is there a way to clear a hung start without restarting the mission? Just had it hang for the first time. I thought it was stable at 20% but not absolutely certain. In any event, the fault needs to be able to be cleared for doing another start and aborting the mission doesn't seem right.
Scratch that, Full shut down of the plane and sitting for a bit clears it. Had it sitting which checking the forum

Edited September 20, 2021 by JeffreyC

[bart]

I recently raised a bug report following an issue I had where I couldn't get the engine to start. Here's a link to that report

 

It now looks as if it wasn't a bug I came across, but due to a change in the start up sequence in a recent update that allows you to get into a hung start situation if you open the HP cock on the throttle a little too early. This led me to look further into the F-16 start up sequence out of pure interest really, as Propulsion was my trade whilst I was in the RAF and I have done countless ground runs on various aircraft IRL during this time, and on each different type of aircraft the sequence was VERY different.

 

So this got my interest going about the sequence of events on starting an F-16 both in our Viper and in real life as far as I could research. Hopefully an ex service F-16 crew chief or someone with real life experience will chime in here to give the "real" low down as far as they would be allowed to do so. 

 

Anyway, I am not 100% sure on this as I have no real life experience with the Viper other than first line refuelling and doing a see in/see off on it. I don't know the ins and outs of how it works. All the aircraft I worked on we were sent on various specialist courses to learn every aspect of the aircraft, how it worked and why, what sequence of events happen and why, in depth systems study etc. We even had to go into flight simulators once a year to get signed off on the ground running aspect, there they would simulate various faults and we would practice how to deal with them in the correct way etc. As for the F-16 I don't have this in depth level of understanding other than what I have read, and gleaned from flying our DCS Viper, but there seems to be a few discrepancies on how the start up sequence works IRL and what we currently have on our Viper.

 

So going back to our start sequence on the DCS Viper, you select "Start 2" the engine spools up to 20% the SEC light extinguishes, you open the HP cock and away you go. Now, if you open the HP cock on the throttle before the SEC light extinguishes you get a "hung" start, and nothing happens. The engine just sits there at 20% with the HP cock open. My question is this, wouldn't the system allow fuel into the engine combustion chamber anyway when the HP cock is opened, and what you should see is a rapid increase in JPT without a corresponding increase in engine RPM (%)?, a sure indication of a hung engine start, the operator would therefore have to shut the HP cock on the throttle immediately and allow the engine to continue to spool to keep the airflow going through the engine to cool it down and get rid of all that extra fuel. On my failed start I had no indication of any rise in JPT (check the track file attached to the bug report above), it was as if I had no fuel going to the engine at all. Now this raises another question... has the Viper got another system whereby it will not allow the fuel to enter the engine even if the HP cock is opened, prior to the SEC light going out and the engine reaching the critical RPM necessary for a full engine start?. I also read somewhere that the SEC light extinguishes at 70% RPM when engine control switches from the SEC (Secondary Engine Computer) to the PRI (Primary) mode, it doesn't go out at 20% as ours does and before the HP cock is even opened and therefore before the engine is actually running. I am not sure what Block version of the F16 this info was applicable too however so this may or may not be relevant to our F16. Systems and sequences of events change with aircraft updates. Here's a link to where I obtained that info from.

How to start the engine on an F-16 Fighting Falcon - Quora

 

So, thoughts gentlemen please. No arguments though please! It would be good to dig into this further and maybe find out if either what we currently have is in fact accurate, or compile some evidence that we could submit to ED to have our Viper updated should the sequence we currently have be incorrect. Either way hopefully we all will have learned something more about the Viper!

Edited October 4, 2021 by bart

[mvsgas]

https://forums.eagle.ru/topic/282066-the-aircraft-will-not-start/

 

https://forums.eagle.ru/topic/282067-hung-start-on-latest-update-is-not-a-real-thing/?tab=comments#comment-4781108

[Devil-101]

The issue is still there; However, I face it in VR mode. F16 RPM gets to 20% when starting the JFS Engine is not starting at all; the only solution I can do is create a plane using Windows+Home

[Falconeer]

you need to wait until rpm gets to just over 20% and stabilize there and the SEC light goes out. After those 2 conditions are met, advance throttle to idle using Shift+Home

[Lord Vader]

Hi @Devil-101

The RPM must reach above 20% to move the throttle to idle. The best procedure, however, is when it goes above 20% look below to the annunciator panel and check when SEC light goes out and then move the throttle lever to idle. If you do that before the SEC light extinguishes, you'll have a hung start.

If you still believe there is an error in the logic, please create a small track for us to observe what you are doing.