A military F-16 fighter jet crashed into a commercial building at March Air Reserve Base in Moreno Valley, California, CBS Los Angeles reported. The pilot ejected and is being evaluated, the Riverside County Sheriff's office tweeted.

The Air Force said the aircraft was assigned to the 114th Fighter Wing out of Sioux Falls, South Dakota and was conducting a training mission.


https://www.cbsnews.com/news/f...?ftag=CNM-00-10aab4i

Glad no fatalities.

Any idea why there was no fire or explosion?

quote:

Originally posted by Icabod:
Any idea why there was no fire or explosion?

I was wondering the same thing. No fuel no fire?

+87 to ^

There was a fire. It was extinguished by the building fire suppression system.

quote:

Originally posted by sns3guppy:
There was a fire. It was extinguished by the building fire suppression system.

That must be one hell of a fire suppression system. I saw video on the news this morning from inside the warehouse. It was quick, but I could not tell there was a fire.

Probably not the answer but if your plane goes down because it ran out of fuel, there's rarely a fire.

quote:

Originally posted by NK402:
Probably not the answer but if your plane goes down because it ran out of fuel, there's rarely a fire.

Only in the movies.

Doesn't the F-16 APU use hydrazine? I'd be real worried about those fumes.

Yes.

The bottle is pretty stout and can survive intact.

Depending on the manner the aircraft impacted.

I suspect it was a flat spin when it hit the roof, and both being flat and the roof structure dissipating energy, it may have been enough to reduce post crash fire.


But if you smell ammonia, you got more than you want.

quote:

Originally posted by Sigmund:
Doesn't the F-16 APU use hydrazine? I'd be real worried about those fumes.

Yes, it does.

Dang, my brother just sent me a picture from inside the building, he was there. He is stationed at McChord, so I didn't even think about him. He was TDY there.

quote:

Originally posted by sns3guppy:
There was a fire. It was extinguished by the building fire suppression system.

I want to meet the people that designed and built that fire suppression system.

Talk about great marketing marterial, you can drop a fighter jet on one of installations and our system will take a lickin' and keep on ticken'.

The link has a stock photo of the defective valves.

https://www.pe.com/2020/04/23/...year-air-force-says/

Hydraulic failure caused F-16 to crash near March base last year, Air Force says

By BRIAN ROKOS | brokos@scng.com | The Press-Enterprise
PUBLISHED: April 23, 2020 at 12:32 p.m. | UPDATED: April 23, 2020 at 6:11 p.m.

Two parts, each less than an inch tall, that failed because they were improperly installed led to the loss of hydraulic pressure, preventing the pilot from controlling a $24 million Air National Guard F-16 that was destroyed when it crashed near March Air Reserve Base last year, according to a U.S Air Force report.

The pilot ejected and parachuted onto the base on May 16, 2019, suffering minor injuries. The Fighting Falcon plummeted through the roof of a warehouse, destroying the jet and causing a small fire. Twelve people in the warehouse were treated for exposure to the debris, the Cal Fire/Riverside County Fire Department said at the time.

The 22-page report, dated April 14 and obtained by this news organization on Thursday, April 23, provides the Air Force’s first publicly announced explanation for the crash.

The document said the two valves were damaged before the crash, causing hydraulic fluid to leak. The valves were part of a flight-control system that was overhauled in January 2019 and installed in the jet after a possible hydraulic leak was discovered several months later.

“By a preponderance of the evidence, the cause of the mishap was the improper installation of two hydraulic check valves … which resulted in the loss of sufficient hydraulic pressure to control the (F-16). A preponderance of the evidence also indicated an inadequate (flight-control system) overhaul process that lacked an effective procedure to identify improper installation of ISA check valves was a substantially contributing factor,” Col. Eric C. Paulson, the president of the accident investigation board, wrote in the report.

ISA is an acronym for Integrated Servo Actuator, the flight-control system.

The jet flew 10 missions after the March 28 installation before crashing.

The F-16 was one of two jets practicing intercept maneuvers 120 miles east of the March base, which sits on the Riverside-Moreno Valley border. The planes were returning to March when the one jet lost hydraulic pressure.

The pilot burned off fuel before ejecting, the report says. The pilot, who is not identified in the report, was found to be healthy, rested and not under the influence of any drugs or alcohol. The report did not blame pilot error for the crash.

The F-16 was assigned to the 114th Fighter Wing at Joe Foss Field in South Dakota and ran missions for the 144th Fighter Wing at March.

The report gave this account of the mission:

The two jets took off from March about 2:10 p.m. and headed east for a one-on-one intercept training mission.

As they returned, the pilot of what the report described as the “mishap plane” received a cockpit warning of a loss of hydraulic pressure in one fluid tank near Palm Springs. The jets are equipped with two fluid tanks, A and B. They operate simultaneously and are designed to back up the other in case one fails.

The pilot, as a precaution, began burning fuel and lowered the landing gear to increase drag. When he did so, he noticed a loss of pressure in the B tank. The pilot was able to align the plane for a straight-in approach to March from 10 miles out. Then, less than a mile from the runway, the plane rolled left. When the pilot tried to counter, the plane rolled hard to the right.

Unable to control the jet, the pilot ejected at 3:39 p.m. about 250 feet above the ground with the plane traveling about 200 mph in a 40-degree bank. The pilot landed on his back off the end of a runway and was dragged by his parachute. The plane crashed into a warehouse on Opportunity Way about a half-mile west of the base. The wings and left horizontal tail were largely intact. The cockpit separated from the fuselage on impact, and the 370-gallon fuel tanks were destroyed, the report said.

Subsequent tests found problems with the inlet check valves — one on each of tanks A and B — that regulate the flow of hydraulic fluid.

Each valve consists of a cap, screw threads, a retainer ring and an O-ring that collectively are referred to as a screw cap. That screw caps screws into the valve body. The retainer helps keep the O-ring in place. It is primarily the screw cap retainer and O-ring that prevent hydraulic fluid from leaking under high pressure.

The investigation determined that both screw caps were not properly screwed into the valve bodies. The retainers were found to be deformed, and the ends of the retainers were spread apart. Also, portions of the O-ring were missing. Near the gap between retainer ends, fragments had torn away from the O-rings, allowing hydraulic fluid to leak out through the threads between the screw caps and the valve bodies.

The report did not say what the Air Force is doing to address the deficiencies noted in the inspections of overhauled equipment. Nor did the report explain why the missiles onboard the jet did not explode, or whether it was a concern about an explosion or exposure to a toxic chemical in the ejection system that prompted authorities to repeatedly push back people who had gathered near the crash scene.

Those questions were put to the Air Force in an email Thursday.

The missiles were eventually taken to Ben Clark Training Center, where they were detonated.

The Air Force said the jet was valued at $24,991,645 and that the environmental cleanup cost was $3,937,652.

Wonder what happened to the mechanic who signed off on this one. $25 Million aircraft and $4 Million

quote:

By a preponderance of the evidence, the cause of the mishap was the improper installation of two hydraulic check valves

The biggest reason I didn't become an aircraft technician.

And people wonder why so many things are designed so that they can’t be done wrong.

Years ago, in a different career, we did an Annual inspection on an old rebuilt WW II trainer, and our IA found that the horizontal stab had been installed upside down. The plane had been flying for years and passed several inspections prior to the discovery...which lead to several ruffled feathers and some finger pointing.

There can be a variety of reasons why an aircraft part can be installed incorrectly; poor training, inexperience, cramped working spaces that often prohibit visually observing an installation/ repair and instead "doing it by feel", poor lighting, or even laziness or lack of attention to detail...the important thing for both aircraft mechanics and air crews to know is that it can happen and plan accordingly.

The seemingly smallest of errors or lack of attention to detail can lead to catastrophic events.

Many of the old timers I flew with would remind me that one of the most dangerous types of flying a pilot will encounter is flying a plane right after it has been released from a repair or inspection. An experienced pilot test flying a plane fresh from repair or inspection will keep it in the pattern for a time while "exercising" it.

Sigmund, I was wondering what the accident investigation would determine what the cause of this crash was so thanks for the follow-up.

I arrived to pick up an airplane following repair, many years ago. I found all the inspection panels on the underside of the wings and fuselage, missing. That raised numerous questions about what else had been missed. This made me especially curious about the report I received, that the airplane had been test flown the night before, and reported nothing amiss.

I rejected the airplane, and returned after it was pronounced "ready." This time, I discovered the fuel tanks bone dry, and asked again about the "test flight." I was assured it had gone well.

When I discovered that the ailerons were rigged backward, I packed my things and went home.

I was sent back for the airplane some time later. On the first flight, the first time I deployed flaps, there was a loud bang and the flaps auto retracted. I landed, parked, and walked away, never to return.

Some years later, different location, I was asked to do a pre-closure inspection on a four-engine bomber, prior to engine runs and a test hop. My assignment was to inspect all four engines and compartments, prior to them being closed up. I was told to "inspect them, but don't find anything." Clearly two different concepts.

I used a notebook to record my findings, which amounted to about fifteen items per engine, including things such as fuel lines not attached. Serious issues. I was confronted by a supervisor who demanded to know why I was taking notes.

I replied that my feeble brain couldn't keep track of that many problems. The supervisor demanded to know what I intended to do with the notes, and told me that he suspected I was secretly making notes "to give to the feds."

I folded up my notes and slipped them in his shirt pocket. I advised him that it was his problem now, I was no longer involved with his project.

The crash of the P-51 "galloping ghost" at Reno a few years ago, which lost control and crashed in the grand stands, killing a number and injuring many, was the result of one tiny little fiber lock nut on the elevator trim tab...a nut that shouldn't have been re-used, but was. It vibrated loose, caused flutter, caused the controls to fully deflect so hard that it knocked the pilot unconscious in the ensuing loop...that terminated in a power dive into the grand stands.

In airplanes, little things become big things: little things count, and details really, really matter.