Jump to content

hung start on latest update is not a real thing


Simba11
 Share

Recommended Posts

1 hour ago, Simba11 said:

Dear ED i dont know who told you that you will get a hung start if you don't stable lize a 20% before going to idle but that's actually not a thing. 

 

You need to start with who told you it is not a thing, what are yours, his or hers qualifications on the matter etc... then after that, when you introduced the source and made it credible you can say this or that is not a thing.

Otherwise who on earth will believe that what you are saying is true?

  • Like 19
Link to comment
Share on other sites

Colleague of mine and former F-16 C/D instructor in the Chilean Air Force completely confirmed this is in fact real…

 

He tells me if engine isn’t sufficiently turned by the time Fuel-on is selected, the N2 will not accelerate and it will hung start.

so, yeah, thanks ED for the realism!

  • Like 11
  • Thanks 1
Link to comment
Share on other sites

3 hours ago, EagleA25 said:

Colleague of mine and former F-16 C/D instructor in the Chilean Air Force completely confirmed this is in fact real…

 

He tells me if engine isn’t sufficiently turned by the time Fuel-on is selected, the N2 will not accelerate and it will hung start.

so, yeah, thanks ED for the realism!


Just to add to that, it’s usually not good for N2 turbine (gas generator) to stay in a hung start condition for too long. Usually leads to thermal damage (similar to a hot start, also bad) and at least an engine inspection. 

  • Like 4

Aircraft: A-10A, F-15C, A-10C, A-10C II, F-14, F-16C, F/A-18C, AH-64, UH-1H, P-47, P-51D, Bf-109, DH Mosquito

Modules: Super Carrier, NTTR, Persian Gulf, WWII Assets

PC: MSI 990FXA Gaming, FX-8120 3.1 GHz, 32GB Patriot Viper RAM, GTX980 4GB, 27" 1080p curved Samsung monitor, TM Warthog HOTAS, Saitek Pro Flight pedals, Opentrack

 

Link to comment
Share on other sites

from what i understood from an F16 captain i talked to at an airshow: the pratt & whitney engine needs a 20rpm stable, but the general electrics engine is able to just walk from 0 to 100 in one go? anyone with better engine knowledge able to confirm or explain further maybe?

Link to comment
Share on other sites

For what is worth, I do not know of anyone IRL ( pilot or maintainer) that has ever tried to move the throttle to idle from cutoff on purpose without RPM being at 20% or higher (PW-220E, 220 or GE-100). I know some that have made a mistake (rushing or not paying attention) that have started the JFS with throttle on idle, but corrected immediately and terminated the start because IRL, starting the engine is a critical thing. Everything happens very fast and you are paying attention to RPM, FTIT, oil pressure, main gen and stand by gen lights. Started the JFS with throttle in idle could raise FTIT rapidly, which is signs of a anticipated hot start. Manuals have a very specific terminology for anticipated hot start we all have to memorize to qualify as an engine run person. This also would be sign of autoaccel condition, also cause you to terminated engine start.

 

So, whom ever said is not a thing IRL, has never been run qualified in USAF on any F-16. GE engines can not go from 0 to 100 and I can't think of anyone would try IRL. In the last couple years I work on F-16 with PW engine (Luke AFB in 2009 to 2011) you had to run the JFS for 2 minutes before going to idle, to allow the bleed strap time to close.

 

So IRL, you pay close attention when starting the engine and this is not a problem. In DCS, people just what to flip switch while drinking coffee and start as quickly as possible to airquake and are not paying attention, the only reason this is a problem.

 

Some will say: "Well, we do not have those engine in DCS" your right, I was never run qualified in GE-129. They can also say: "You have never started the JFS with throttle in idle, so you don't know what will happens". Again you are right on that also.


Edited by mvsgas
spelling
  • Like 6
  • Thanks 3

To whom it may concern,

I am an idiot, unfortunately for the world, I have a internet connection and a fondness for beer....apologies for that.

Thank you for you patience.

 

 

Many people don't want the truth, they want constant reassurance that whatever misconception/fallacies they believe in are true..

Link to comment
Share on other sites

People with enough engine knowledge will know to high certainty what will happen without actually doing it. There exists someone who knows the GE129 inside and out and can say "oh well yeah you won't get any start because there's a special interlock that inhibits fuel if commanded idle with less than 13.37% RPM" or "I dunno, you'd probably get a fire dumping in fuel at low RPM when ignition hit the pool sitting in the bottom of the chamber."

Link to comment
Share on other sites

Correct me if I’m wrong, but also isn’t it proper procedure to make sure the SEC annunciation goes out before going to idle? Not just stable 20%?


Sent from my iPhone using Tapatalk Pro

  • Like 4

Win 10, AMD FX9590/water cooled, 32GB RAM, 250GB SSD system, 1TB SSD (DCS installed), 2TB HD, Warthog HOTAS, MFG rudders, Track IR 5, LG Ultrawide, Logitech Speakers w/sub, Fans, Case, cell phone, wallet, keys.....printer

Link to comment
Share on other sites

2 hours ago, Eagle7907 said:

Correct me if I’m wrong, but also isn’t it proper procedure to make sure the SEC annunciation goes out before going to idle? Not just stable 20%?

 

That's how I do it too.

Intel i7-4790K @ 4x4GHz + 16 GB DDR3 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

Link to comment
Share on other sites

Please correct me but i thought so far that throttle Inputs are handed from the Cockpit to a Computer and then to the engine and therefore setting the throttle to idle too early does Nothing as the computer will only start up the engines in the proper conditions. I have No sources for that but i Wonder why the digital Interface has Not been discussed Here yet. Maybe in Startup the Computer System is Not running yet or bypassed for safety reasons?

Link to comment
Share on other sites

 

  • Like 1

To whom it may concern,

I am an idiot, unfortunately for the world, I have a internet connection and a fondness for beer....apologies for that.

Thank you for you patience.

 

 

Many people don't want the truth, they want constant reassurance that whatever misconception/fallacies they believe in are true..

Link to comment
Share on other sites

Interesting. After viewing the linked thread, since some people labeled some posts on there for scrutiny, I decided to look at a document that can’t be posted that seems to be referenced by many. I will tell you that it doesn’t really mention the words “stabilized”, but it does mention 20% minimum, and also includes maximum rotation speed when ambient temps above 90 degrees F. The SEC is mentioned, but doesn’t specifically say wait until SEC light goes out. It just says the light goes out reaching 20%. So in another way of thinking this, you would wait until it goes out? I think it doesn’t particularly say this because of the conditions that would warrant a later activation from OFF to IDLE.

FYI, this is particularly pertaining to the -129 engine.


Sent from my iPhone using Tapatalk Pro

Win 10, AMD FX9590/water cooled, 32GB RAM, 250GB SSD system, 1TB SSD (DCS installed), 2TB HD, Warthog HOTAS, MFG rudders, Track IR 5, LG Ultrawide, Logitech Speakers w/sub, Fans, Case, cell phone, wallet, keys.....printer

Link to comment
Share on other sites

On 9/21/2021 at 12:01 AM, Badlego said:

Please correct me but i thought so far that throttle Inputs are handed from the Cockpit to a Computer and then to the engine and therefore setting the throttle to idle too early does Nothing as the computer will only start up the engines in the proper conditions. I have No sources for that but i Wonder why the digital Interface has Not been discussed Here yet. Maybe in Startup the Computer System is Not running yet or bypassed for safety reasons?

There are two input to the engine, Main is throttle position switch that sends Power Lever Angle (PLA) to the Digital Engine Computer (DEC). The second input is physical push/pull wire the connects the throttle control linkage on the Main Engine Control (MEC). This is the only physical connection to any control in the F-16 (any versions). The DEC is like you car engine Electronic Control Module (ECM). The MEC is like very complicated carburetor (not even close in reality, but same concept )

 

The DEC nor the MEC  will prevent you from introducing fuel to early to the combustion chamber AFAIK. Other aircraft the start is very automatic, for example A-10 seem way easier. But in the F-117, F-15 and F-16 you can't just put throttle to idle and hit start.

  • Like 2

To whom it may concern,

I am an idiot, unfortunately for the world, I have a internet connection and a fondness for beer....apologies for that.

Thank you for you patience.

 

 

Many people don't want the truth, they want constant reassurance that whatever misconception/fallacies they believe in are true..

Link to comment
Share on other sites

 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...