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TangoandCash wrote:The video is almost like watching a crash in slow motion. My uneducated guess is something related to the lift fan (mechanical, engine, software, who knows), resulting in the bounce and nose landing. Why the pilot or computer didn't cut the power at that point I have no idea, maybe it was related to the reason for the bounce.
Ejection does seem to come very late in the sequence, but I wasn't along for the ride.
aumaverick wrote:Oh, I hope this wasn't another instance like the OK F-16 incident. I know the safety of the pilot is paramount, but when the aircraft comes down in one piece near the runway, it leads to a lot of questions why the pilot couldn't also come down in one piece with the aircraft.
https://www.airforcetimes.com/news/your-air-force/2022/12/02/fighter-pilot-who-tailed-a-civilian-plane-blamed-for-destroying-f-16/
TangoandCash wrote:The video is almost like watching a crash in slow motion. My uneducated guess is something related to the lift fan (mechanical, engine, software, who knows), resulting in the bounce and nose landing. Why the pilot or computer didn't cut the power at that point I have no idea, maybe it was related to the reason for the bounce.
Ejection does seem to come very late in the sequence, but I wasn't along for the ride.
GalaxyFlyer wrote:TangoandCash wrote:The video is almost like watching a crash in slow motion. My uneducated guess is something related to the lift fan (mechanical, engine, software, who knows), resulting in the bounce and nose landing. Why the pilot or computer didn't cut the power at that point I have no idea, maybe it was related to the reason for the bounce.
Ejection does seem to come very late in the sequence, but I wasn't along for the ride.
Just a guess from an ejection seat survivor, he waited until somewhat upright. Some of the attitudes were likely out of the envelope until it settled back on the main mounts.
The drop from about 100’ looks fast like it was settling under power and the sink couldn’t be arrested. Impact was probably pretty firm judging from sink rate and bounce. Once the nose mount failed, the attitudes got pretty steep, I’m guessing an experienced Lockheed pilot who knows the seat envelope pretty well.
Vintage wrote:It almost looks like the shock of the ejection finally caused the engine to shut down.
Max Q wrote:The descent rate prior to initial touchdown didn’t look that high to me, looked like a normal touchdown, it all seemed to go wrong after that bounce
Perhaps the engine automatically shuts down when the pilot ejects ?
Not much point in it running after that..
Heinkel wrote:Max Q wrote:The descent rate prior to initial touchdown didn’t look that high to me, looked like a normal touchdown, it all seemed to go wrong after that bounce
Perhaps the engine automatically shuts down when the pilot ejects ?
Not much point in it running after that..
On every modern car, when a crash is detected and the airbags are triggered, the ignition is automatically switched off and the main power cable to the battery is cut off by a small pyrotechnic device. In addition, the brake system becomes pressurized.
Should be the same on an a/c with ejection seats. When the ejection seat(s) are triggered, everything else should be switched off automatically.
GalaxyFlyer wrote:I saw elsewhere, Martin-Baker does activate the “auto eject on STOVL model only”. Looking at the video, until touchdown there was no attitude excursion that should activate auto ejection—pretty much upright and level until the pitch excursion followed by nose mount failure. I’d guess auto eject is NOT armed on the ground.
GalaxyFlyer wrote:Remember the massive gaggle of Phantoms out of Hollomon, IIRC, who were meet north of Jever by Luftwaffe Phantoms and the whole 16+ ship formation penetrated weather on the descent—at least one mid-air ensued. In one plane the back seat initiated the ejection without telling the pilot. Both survived but the NAV was severely chastised for acting as PIC.
superbizzy73 wrote:Post # 23 covered that topic.what could cause it to pivot like it did at the end? Seems some funny business going on with the lift fan (just my non-expert opinion).
889091 wrote:In the Twitter video, I did not see the canopy pop - did he eject through the canopy?
Vintage wrote:superbizzy73 wrote:Post # 23 covered that topic.what could cause it to pivot like it did at the end? Seems some funny business going on with the lift fan (just my non-expert opinion).
bpatus297 wrote:Heinkel wrote:Max Q wrote:The descent rate prior to initial touchdown didn’t look that high to me, looked like a normal touchdown, it all seemed to go wrong after that bounce
Perhaps the engine automatically shuts down when the pilot ejects ?
Not much point in it running after that..
On every modern car, when a crash is detected and the airbags are triggered, the ignition is automatically switched off and the main power cable to the battery is cut off by a small pyrotechnic device. In addition, the brake system becomes pressurized.
Should be the same on an a/c with ejection seats. When the ejection seat(s) are triggered, everything else should be switched off automatically.
I don't know how accurate your statement is. First, I have never seen a pyrotechnic device on a car. Second, how can the brake system pressurize with out either a mechanical or electrical power source? I have dealt with my share of vehicle accidents have never seen this. Is this just EV's? Admittedly, I have zero information on their workings.
GalaxyFlyer wrote:Anyone interested in informed detail, check this link.
https://www.f-16.net/forum/viewtopic.php?f=22&t=58979
Heinkel wrote:bpatus297 wrote:Heinkel wrote:
On every modern car, when a crash is detected and the airbags are triggered, the ignition is automatically switched off and the main power cable to the battery is cut off by a small pyrotechnic device. In addition, the brake system becomes pressurized.
Should be the same on an a/c with ejection seats. When the ejection seat(s) are triggered, everything else should be switched off automatically.
I don't know how accurate your statement is. First, I have never seen a pyrotechnic device on a car. Second, how can the brake system pressurize with out either a mechanical or electrical power source? I have dealt with my share of vehicle accidents have never seen this. Is this just EV's? Admittedly, I have zero information on their workings.
There are lots of pyrotecnic devices in modern cars. Several airbags for example. Plus the electric cut-off switch.
The brake system pressure after a crash is provided by a hydraulic pressure accumulator. The system is called PCB = Post Crash Braking.
https://www.continental-automotive.com/en-gl/Passenger-Cars/Safety/Functions/Integrated-Safety/Post-Crash-Braking
bpatus297 wrote:The Pyro fuses you are talking about are in EVs, not "every modern car"
and air bags are inflated with nitrogen gas from a chemical reaction, not pyro.
teampokey wrote:bpatus297 wrote:The Pyro fuses you are talking about are in EVs, not "every modern car"
Low-voltage pyro fuses appear in some non-EV cars—I found Audi and Mercedes models—although "every modern car" might be an overstatement.and air bags are inflated with nitrogen gas from a chemical reaction, not pyro.
Airbags often use a pyrotechnic ignitor or a pyrotechnic valve, even if you don't consider a particular gas-generating reaction to be a pyrotechnic one.
bpatus297 wrote:Heinkel wrote:bpatus297 wrote:
I don't know how accurate your statement is. First, I have never seen a pyrotechnic device on a car. Second, how can the brake system pressurize with out either a mechanical or electrical power source? I have dealt with my share of vehicle accidents have never seen this. Is this just EV's? Admittedly, I have zero information on their workings.
There are lots of pyrotecnic devices in modern cars. Several airbags for example. Plus the electric cut-off switch.
The brake system pressure after a crash is provided by a hydraulic pressure accumulator. The system is called PCB = Post Crash Braking.
https://www.continental-automotive.com/en-gl/Passenger-Cars/Safety/Functions/Integrated-Safety/Post-Crash-Braking
The Pyro fuses you are talking about are in EVs, not "every modern car", and air bags are inflated with nitrogen gas from a chemical reaction, not pyro.
https://auto.howstuffworks.com/car-driv ... irbag1.htm
I didn't know about PCB or AEB. It looks like it is really new, but comes standard all about 99% of.new vehicles sold.
bpatus297 wrote:teampokey wrote:bpatus297 wrote:The Pyro fuses you are talking about are in EVs, not "every modern car"
Low-voltage pyro fuses appear in some non-EV cars—I found Audi and Mercedes models—although "every modern car" might be an overstatement.and air bags are inflated with nitrogen gas from a chemical reaction, not pyro.
Airbags often use a pyrotechnic ignitor or a pyrotechnic valve, even if you don't consider a particular gas-generating reaction to be a pyrotechnic one.
When you say pyrotechnic I think an explosion (no matter how small). Most airbags use a chemical reaction to create nitrogen gas. Yes, I know.an explosion is a chemical reaction, but you know.what I mean.
A source familiar with the program, who spoke on the condition of anonymity because they were not authorized to discuss details of the incident, said the initial assessment of the investigation, which is being conducted by the Naval Air Systems Command with the support of the JPO, found that a propulsion system issue led to the Dec. 15 crash of the hovering F-35B, which has now led to broader groundings in the fleet.
The source said that, in guidance to the services, the JPO said a failure of a tube used to transfer high-pressure fuel in the fighter’s F135 engine prompted the office to update its safety risk assessments.
Though the JPO would not say exactly how many F-35s were grounded, it confirmed the grounded jets include all three variants. Some of those grounded F-35s are American fighters.
889091 wrote:Think we can rule out the lift fan (for now, at least). From the link that art provided:Though the JPO would not say exactly how many F-35s were grounded, it confirmed the grounded jets include all three variants. Some of those grounded F-35s are American fighters.
Dutchy wrote:889091 wrote:Think we can rule out the lift fan (for now, at least). From the link that art provided:Though the JPO would not say exactly how many F-35s were grounded, it confirmed the grounded jets include all three variants. Some of those grounded F-35s are American fighters.
This F-35B wasn't delivered yet, right? So we might conduct that it is the latest batch of F-35's would be affected, or better their engines?
TangoandCash wrote:Ejection does seem to come very late in the sequence, but I wasn't along for the ride
Mikenike wrote:1. From reports the linkage between the fan and the main engine had a failure causing a loss of thrust, which explains the sudden extreme forward pitch in a consistent manner. As for why the jet didn't recognise the issue and attempt to fix, who knows.
Mikenike wrote:
I remember reading an initial report from a reliable source, but I can't seem to find the report online anywhere. With that being said, I distinctly remember reading it and it clearly detailed the incident and the initially believed cause they outlined was a failure in the linkage. I remember it saying it had a smaller failure in a supporting system that caused the failure, but I can't remember the exact thing that was the catalyst for the linkage failure.
This report could have been pure speculation based on the information availible, and they could have already disproven the report (and by extent my) claims that it was a linkage issue. Whatever the reason the facts are clear, the fan went idle/shut down for some unknown reason to the public at this time, the resulting unplanned descent caused a hard bounce followed by a downward pitching of the nose, causing a hard impact on the nose gear, ensued by a hard landing where the jet spun, and when it finally righted itself, followed by an immediate firing of the pilot's ejection seat, resulting in a successful ejection and a full chute before the pilot hit the deck. Thankfully he isn't too badly injured (ICU Level hurt) or killed by this, and hopefully LM and F-35B operators can develop an emergency procedure for this type of incident.