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Comment by Manuel_D | Hacker News Reader

> Del Pizzo’s F-35B malfunctioned and its primary displays and communications cut out as Del Pizzo was attempting to land through rain at Joint Base Charleston, South Carolina. However, the report said its standby flight display and backup communication system “remained basically functional.”

> The report said Del Pizzo followed the F-35B manual’s recommendations for ejecting from an out-of-control jet but also criticized the manual’s definition of out-of-control as too broad.

It sounds like the displays blacked out, but radios and flight controls still worked. This is still definitely an aircraft that can land safely.

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That really, really depends on what conditions you are flying under. This is not a naturally stable aircraft flown at relatively low speeds far away from any obstacle, and it is not being flown from a couch with a gamepad.

Even if he fucked up severely and needlessly burned an insanely expensive asset at the cost of tax payers, that’s a fuckup from an individual actually qualified for and skilled at flying the thing, unlike everyone at this site.

The whole lot of us would probably have the plane go up in flames before we even got into it.

The flight control software was not malfunctioning. He had instruments and communication capability that would have let him land an otherwise flyable aircraft.

Again, a very easy judgement to make when you’re not the one strapped to the rocket in what the documents describe as “challenging conditions” as your displays you were flying after go dark.

He only had “basically working” comms, which seems to suggest that it too was degraded, and the instruments referred to as being available is just the tiny artificial horizon display in front of his right knee.

I've been strapped to such a rocket in such challenging conditions with even worse remaining operable equipment more than once.

The radios did not work. One was out, the other was “basically functional.” At 2000 feet, while in VTOL mode, how long do you have to figure out if your backup radio is “basically functional”? And to evaluate whether the standby flight display was working properly? And to figure out whether the plane is accelerating up and out of VTOL mode like you told it to or heading toward the ground?

The F35 does not have a dedicated radio control panel. It's a menu driven operation through a multi function display. More damningly these electrical overload failures are known on the platform.

The plane is just a poorly designed death trap.

> This is still definitely an aircraft that can land safely.

This is not a prop plane. It's a heavy jet which should be almost stalling to land safely. Tower guys can roughly guide you on the course and speed but there would be at least 1-2 seconds lag between the reading, reading and acting. I wouldn't say what you can "definitely land safely" in these conditions.

Interesting detail in TFA is that the pilot had converted to the plane's short take off and vertical landing mode, but instead carried out a missed approach procedure when his helmet-mounted display malfunctioned.

What do you mean by "instead"? Would you have expected the pilot to guess where the runway is without his instruments? He was flying in IMC. Meaning he couldn't see where he was going.

I’ve never flown an F35. From what I understand they’re basically rockets that “fly” because of software that makes micro corrections several times per second.

Maybe if the screens are out the pilot couldn’t rely on that?

No, the screens are a separate system from the fly–by–wire computer. You don’t throw your desktop computer out of a window just because one monitor goes out. You use the other monitor to order a replacement from IT or Newegg or whatever. In this case the F–35 has three independent displays that can all redundantly display the same information: the HUD in the pilot’s helmet, the primary display, and the standby display. The standby display is smaller and below the primary display in the cockpit, but it is designed to keep working even when everything else doesn’t. Their whole purpose is to be the backup in case the other displays fail.

> In this case the F–35 has three independent displays that can all redundantly display the same information

This is not true. The standby display is just a tiny artificial horizon by the pilot's right knee, so when HUD and primary display is out, all you're left with is your speed, altitude and attitude. This cannot in any way or form be considered "the same information" as the primary flight display of an F35B, and leaves you without a lot of control.

Whether you can limp along with such backup system depends entirely on what is going on at the time the primary flight displays go dark. In a fighter jet, that display may in some cases just tell you what angle and velocity you are going to die at. Furthermore, in challenging conditions you might have to make a decision very quickly and might not have time tuning yourself into the standby display and its degraded information.

This type of degraded backups exist in many aircrafts - you don't want the pilot of an Airbus you're in to be confronted with the plane dropping to mechanical law, or even direct law if taking off or landing, even if these modes are technically flyable and well documented.

The standby display is only “tiny” in comparison to the primary flight display, which is a 25” LCD panel. It’s actually the same size as the artificial horizon in most general aviation planes. The information shown on it was not degraded in any way. The accident investigators concluded that the pilot could have and should have relied on it to fly the plane. He just didn’t.

Furthermore, it’s not appropriate to compare the standby instruments with the alternate control law of Airbus airliners. I don't know if the F–35 has anything comparable with Airbus’s alternate law or direct law, but if it does it wasn’t activated during this incident. The pilot did not experience any loss of control of the aircraft.

But I agree with you that a lot of incidents involving Airbus aircraft have been related to alternate law. Pilots get caught out by it all the time, apparently.

As said elsewhere, it’s not that a plane can be kept in level flight with an artificial horizon that matters. As with the airbus pilots, it’s the surprise - especially when it happens in already stressful situations.

In this case we’re also dealing with an instrument SVTOL landing in terrible weather which cannot be flown with just an artificial horizon, repeated electrical failures in a short timespan, a disbelief that the aircraft correctly reverted from SVTOL to winged flight mode with all relevant instruments to confirm out - as the site says, “extremely challenging cognitive and flight conditions”. And, a manual that says if the aircraft goes out of control at low altitude, you must eject.

At a high altitude cruise it could have been flown just fine by the horizon while things get diagnosed and possibly diverted to a landing suite suitable for the remaining equipment.

> ... all you're left with is your speed, altitude and attitude.

Which is all you need. You have the same information in any other aircraft, most only have airspeed and altimeter info. An attitude indicator is of great help when you're flying through clouds so you can check that you're actually flying in level flight - it is pretty weird to find out you're actually flying banked but because you have coordinated flight you don't feel it.

Have you flown a modern fighter jet while suddenly your helmet integrated flight displays and navigation went out and you had to reorient yourself and rely entirely on nothing but your knee-mounted false horizon mid-maneuver, while attempting instrument landing under - and I quote - “extremely challenging cognitive and flight conditions” where you due to repeated electrical glitches have lost faith in the aircraft and in particular its ability to transition back from SVTOL to regular flight operation? Because that was the situation that you claim was fine.

You can keep an otherwise fully functional aircraft in stable level flight using a horizon, but that’s neither interesting nor relevant. This was not a lightweight aircraft cruising above the clouds with nothing around it.

Setting correct pitch and power using the standby instruments should be enough then?

Seen on the lower right part of the center console: https://img.militaryaerospace.com/files/base/ebm/mae/image/2...

Do you know what CFIT is?

The problem seems to be a pilot from AZ unaccustomed to flying in heavy rain with insufficient practice using the backup instruments.

The pilot is from Atlanta, GA. His assignment to VMX-1 in Arizona happened after the investigation as noted in the article.

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