Strong King Air

Check out this story and look at their track log.

kfvs12.com/ (sorry could only link their homepage but it is the top story)

flightaware.com/live/flight/N777 … /KROG/KCGI

That’s a very interesting TV video clip. Thanks, Falcon1.

The FA flight log shows 1 minute from 27,000 ft to 7800 ft. Amazing!

I was just going to post a new topic about this. (you a PPW member falcon1?)
Holy crap that’s amazing.

Wow! That is amazing on every level. Nobody hurt, perfect ending.

PPW?

If that is Pro Pilot World than I’m not

Perfect ending would be no damage to the aircraft. Somebody’s gotta pay for the damage to the wings and elevators - and of course the windshield.

A Southeast Missourian newspaper article is available here that provides some additional information about the events leading up to this emergency landing incident.

There are a couple things I don’t understand with this story. First is why neither of the crew were able to get their oxygen masks on. The Time of Useful Consciousness (TOC) at FL 250 is 3 to 5 minutes, at FL 280 2.5 to 3 minutes. Note:A rapid decompression can reduce the TUC by up to 50 percent caused by the forced exhalation of the lungs during decompression and the extremely rapid rate of ascent.] So hell, even if it was one minute, they should have been able to get the masks on before “passing out.” Edit: Just found this comment over at aero-news,

"Pilot Stone told local media that “We were both getting drunk really fast. I remember thinking, really slowly, ‘Hey, I’m not getting any oxygen, what’s wrong here?’ But I was so loony already at that point I couldn’t even solve the problem if it could be solved. I just sort of thought to myself, ‘I’ve got to hurry,’ but everything was fading.”

Second is why they lost pressurization in the first place. A spiderwebbed windshield is not usually cracked all the way through, just one layer of glass; no loss of pressure.

I’d be very interested to hear what the NTSB says about this.

James,

According to the story linked by dcgreen, the crew initiated depressuration for fear the cracked windshield would “blow out”. If I read that story correctly, they waited until after depressurizing to reach for the masks, only to find out that there was no O2.

Are cracked windshields a common problem in the King Air? I’ve heard of it happening several times. Not quite to this extent of course!

Windscreens can crack when cold, and the anti ice is turned immediately to high. Also could be a small pebble ping, not visible, that just starts to spider when the extra pressure from high speeds starts pushing.

So much for preflighting the O2 system. Also in the 200 there is a O2 control knob behind the crew on the overhead. If this knob is not pulled out then no flow. Easy to forget if you don’t use the checklist or don’t arm the system on a constant basis.

First off the B200 doesnt have an overhead valve like the C-90. Second, I can tell there are people"sounding off"who obviously have never been hypoxic at those altitudes, 3 to 5 minutes my rear, thats a good dream,but reality is much different. TOC is greatly reduced by many variables. I dont mean to jump on anyone’s case, but the whole monday morning quarterback speculation is absurd.

Older 200’s do in fact have O2 knobs behind the pilots on the overhead. I welcome you to come by and I can show you.

It’s what we do best!

Welcome to the Asylum.

What do you think caused the crew’s accelerated TUC?

Ohhh where to begin, where to begin… Why wasn’t the oxygen system armed before they got to FL270? What on earth made it seem like a good idea to “depressurize” to a/c? Just goes to show you, sometimes it’s better to be lucky than good!

Could this be a checklist item?

It would make sense to me to equalize the pressure on both sides of the glass. Pumping up the cabin might blow it out.

The glass is a laminate and, while it’s relatively common to lose integrity in the inner or outer glass, it’s pretty rare for an aircraft to shed the glazing entirely and suffer an explosive decompression.

Hence, I have to question the flight crew’s decision to depressurize the aircraft so rapidly as to result in their loss of consciousness. What does the B200 AFM say is the proper method to address this?

From a BE20 manual.
Emphasis mine.

Outer Panel cracked, no pilot action is required. Wiper may be damaged if you try to use them and heating element may be inop in the area of the crack.

Inner Panel cracked, Reset pressurization controller to 4 psi or Lower (within 10 minutes). Descend if necessary for 4 psi. Even though it doesn’t say it, land as soon as practical.
Cracked Cabin window, reset pressurization controller to 4.6 psi or lower.

4psi differential in 10 minutes is pretty benign. Definately doesn’t call for dumping the cabin, especially before ensuring your O2 is working!

I don’t know about the B200, but when I flew a 1900 we could fly with a cracked windshield. The MEL (minimum equipment list) said that the cabin pressure had to be between a certain differential. I don’t remember the numbers but I think it was something like between 2.1 and 3.4. Im sure that the King Air has something similar.

As far as the procedure when this happens, I know that we didn’t have any memory items for this, but I think it is in the QRH. And I am 99.9% sure that they never got training on something like this. I have heard that when it happens it’s very loud and scares the crap out of you. Too bad they didn’t put their masks on first per the emergency decent/rapid decompression checklist but they didn’t know what would happen and though they were making the best choice in a split second decision. Awesome that they survived and this is a great learning situation for other pilots.