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-   -   F16 engine error (https://www.pprune.org/military-aviation/601151-f16-engine-error.html)

AmericanFlyer 27th Oct 2017 04:52

F16 engine error
 
Air Force loses $22M F-16 due to engine assembly error - CNNPolitics

Capn Bloggs 27th Oct 2017 05:05

Afterburner on steroids...

dr dre 27th Oct 2017 06:11


Tragic Error

The pilot was able to safely eject and did not sustain any injuries but the aircraft was destroyed as it hit the ground.
Why use the term "tragic" if no people were killed or injured?

Smilin_Ed 27th Oct 2017 09:46


An investigation into the mishap revealed evidence that "the main engine control was missing a required 600-degree training ring and the anti-rotation pin," according to the Air Force.
Back to the subject at hand: Could this have been a "retaining ring"?

PDR1 27th Oct 2017 10:16

I love the comment in the article reference in the OP:


Large portions of the aircraft, including a wing and the fuselage, were found intact after the crash, allowing investigators to identify it as an F-16,
Wow! Lucky to have such experts available!

:E

[and yes, I do appreciate that it's just a stupid comment by a less-than-expert journo, but it made me laugh!]

F-16GUY 27th Oct 2017 10:26


Originally Posted by Capn Bloggs (Post 9937830)
Afterburner on steroids...

It wasn't even in afterburner when the engine ran away. Just goes to show how much higher temperature translates to more power. We had an engine, although a PW one, go 50 degrees past max FTIT for a few seconds, and the pilot described it as getting a kick in the back. The one in this incident went something like 200 degrees plus past its maximum, resulting in plenty of thrust for a short time, and then a melted turbine section as the pictures in the accident report clearly show.

The F-16 is equipped with a max power switch that is in place for war/emergency use only. Engaging it will allow the FTIT to increase by 20 degrees for a short duration of time giving more thrust for a bugout or what have you. It also reduces the engine overhaul time from 600 hours to just 6 hours...

The use of new and more heat resistible materials in engines translates into more power or more hours between engine overhauls. The PW -232 could achieve in excess of 32.000 lbs of thrust compared to the PW -220's 25.000 lbs without any major aircraft modifications (F-16), and it could reach 37.000 lbs with a redesigned intake. That would almost get you a 1 to 1 thrust/weight in a fully combat loaded jet. Just imagine....

number0009 27th Oct 2017 10:57


Originally Posted by Smilin_Ed (Post 9938026)
Could this have been a "retaining ring"?

Yes, you have that right. Apparently the MEC was replaced a couple of days prior to accident.

AIB Report:
http://www.airforcemag.com/AircraftA...16_Andrews.pdf

Records indicated the mishap engine (ME),
serial number (S/N) 509307, went through a modernized digital engine control (MDEC) upgrade
to comply with TCTO 2J-F110-838 on 31 March 2017, and had accumulated 0.0 flight hours prior
to the mishap
(Tabs D-25 and U-3 to U-4).

Engine Shop received the overhauled MA MEC from
the supply system on 3 April 2017, and MA MEC was installed on ME S/N 509307 and passed an
operational engine run test on 4 April 2017 (Tabs D-13, D-23, and J-4).

600-degree spiral retaining ring

melmothtw 27th Oct 2017 13:49


I love the comment in the article reference in the OP:

Quote:
Large portions of the aircraft, including a wing and the fuselage, were found intact after the crash, allowing investigators to identify it as an F-16,
Wow! Lucky to have such experts available!

[and yes, I do appreciate that it's just a stupid comment by a less-than-expert journo, but it made me laugh!]
From the article (bold mine): Large portions of the aircraft, including a wing and the fuselage, were found intact after the crash, allowing investigators to identify it as an F-16, police said at the time of the incident.

Perhaps your guffawing should be directed at the Maryland Police, rather than the journo.

scifi 27th Oct 2017 16:57

Quote.... That would almost get you a 1 to 1 thrust/weight in a fully combat loaded jet. Just imagine....


WOW, I am just imagining.... That would make it able to hover like a Helicopter...!!
.
.Or like a Harrier...

lomapaseo 27th Oct 2017 19:23

Agree that more fuel than wanted means more temperature in the turbine and rapid wear-out. However, it also means more RPM and if it meters passed that emergency response line it may drive the rpms into very bad vibratory modes and fatigue of the disks in very short order.

Such possibilities will require full strip and replacement if confirmed via recorders. In this case with the plane crashed I doubt anybody is looking to reuse anything :0

F-16GUY 27th Oct 2017 20:00


Originally Posted by scifi (Post 9938456)


WOW, I am just imagining.... That would make it able to hover like a Helicopter...!!
.
.Or like a Harrier...

Why imagine something ugly if you can imagine something cool? BTW, I didn't know the Harrier could hover with a full combat load...

F-16GUY 27th Oct 2017 20:10


Originally Posted by lomapaseo (Post 9938589)
Agree that more fuel than wanted means more temperature in the turbine and rapid wear-out. However, it also means more RPM and if it meters passed that emergency response line it may drive the rpms into very bad vibratory modes and fatigue of the disks in very short order.

Such possibilities will require full strip and replacement if confirmed via recorders. In this case with the plane crashed I doubt anybody is looking to reuse anything :0

On the PW engine the DEEC will normally try to maintain the RPM within limits despite the higher temperature, by closing the nozzle. The GE probably does the same, but the amount of fuel was probably so great that the RPM still went above 110%. The pictures show that all the blades on one of the turbine wheels have lost the outer one third. They look as if they have melted away.

NutLoose 27th Oct 2017 20:18

Didn't the early Tornado used to runaway if you lost the computers?

F-16GUY 27th Oct 2017 20:30


Originally Posted by NutLoose (Post 9938628)
Didn't the early Tornado used to runaway if you lost the computers?

Yep, never trust electrical components made by LUCAS!!! Reminds me of my dads old Matchless bike....

Vendee 27th Oct 2017 21:03


Originally Posted by NutLoose (Post 9938628)
Didn't the early Tornado used to runaway if you lost the computers?

Still does AFAIK. Not only did the engine lose its top speed governor, it lost its controlled rate of acceleration so it went to overspeed very, very quickly..... and then went quiet. I can't remember the details but they lost a GR1 quite early on when the pilot was groping for the wander lamp at night and operated the crash bar by mistake. Both gennys and the battery gone, followed quickly by both engines and a Martin Baker tie for the crew.

OK465 27th Oct 2017 21:19

Oh, the good old days of fuel metered directly by pilot throttle movement in those old centrifugal flow engines. :}

Stu666 27th Oct 2017 21:57


Originally Posted by PDR1 (Post 9938066)
I love the comment in the article reference in the OP:



Wow! Lucky to have such experts available!

:E

[and yes, I do appreciate that it's just a stupid comment by a less-than-expert journo, but it made me laugh!]

And there was me thinking it was an SR-71 :E

tdracer 28th Oct 2017 01:26


Originally Posted by OK465 (Post 9938678)
Oh, the good old days of fuel metered directly by pilot throttle movement in those old centrifugal flow engines. :}

Wouldn't make much difference if the fuel control was assembled incorrectly...

Don't they do an engine check run after replacing fuel control components? I'd think that would be mandatory, especially on a single engine aircraft.

Fonsini 28th Oct 2017 02:02

It must be a strange experience to pull back on the throttle and experience an increase in thrust. Whoa horsey.

OK465 28th Oct 2017 14:05


Wouldn't make much difference if the fuel control was assembled incorrectly...
Oh, the good old days of fuel control mx done by mechanics....not IT guys.


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