Citation Down in SW Virginia

[OneHungLow]

It's all very well talking about useful consciousness times, but the problem is that unless you have experienced hypoxia you do not know what your personal syptoms are. That is why the military put you through it under controlled conditions.

My useful consciousness time varies at sea level these days!

I was offered the opportunity of experiencing the hypobaric chamber thing some years ago, but passed on it as really wasn't relevant to me and I need to hang onto the few neurons that I have left.

[Boac]

As Mrs ex-A says, you cannot fart around (pun intended for explosive decompression passengers...) with times of useful consciousness. Hypoxia renders the brain incapable of logical thought processes and while one dilly-dallies around drawing elephants one risks death. Oxy on asap.

[OneHungLow]

I posted the table as a statement of general interest, showing medians and general guidelines really and I am certainly not suggesting that one should reach for a table when one suspects that one might be in situation where hypoxia might be a risk. As folks here are saying, getting on the the O2 ASAP if you can, or reducing altitude ASAP is clearly the only way to go.

I guess "faffing" with tables would be nearly as silly as looking at a table of CO concentrations when one suspects that one might be at risk of CO poisoning, which is a pretty unpleasant thing and one that I have briefly and mildly experienced in flight, although I am aware that hypoxia, can be a more insidious warm fuzzy thing, apparently less unpleasant for some, but equally, and rapidly, deadly while the sufferer may not really appreciate how dire the degeneration of their cognitive and motor faculties has become.

I guess the divers here will be aware of nitrogen narcosis (raptures of the deep) which apparently can be, for some, a very pleasant way to go rapidly to heaven or to hell but I digress.

[Boac]

or reducing altitude ASAP is clearly the only way to go.

Not a practical solution unless you have no oxygen.

[PHXPhlyer]

The altitude was reduced rapidly at the end of the flight ~ 30,000 fpm.
Although, from reports of contact lost with ATC 15 minutes after TO and ~3.5 hours at altitude the rapid reduction of altitude did nothing except contribute to the RUD of the Citation.

PP

[Boac]

Yes - that worked well..............

[G~Man]

It's all very well talking about useful consciousness times, but the problem is that unless you have experienced hypoxia you do not know what your personal syptoms are. That is why the military put you through it under controlled conditions.

I did the chamber many many years ago in my former life. They took us up to 25,000' on oxygen and then 2 by 2 we removed the mask and performed various mental tasks. At about the 2 minute point, we were given a number to remember and then told to put our masks back on. No-one remembered the number once back on O2.... I do remember having issues counting backwards etc.... Very interesting experience.

I can say that unless you knew you had the onset of hypoxia from some opther source of information, you would never realize it, and you would "slump over".

This is worth a watch:

[OneHungLow]

or reducing altitude ASAP is clearly the only way to go.

Not a practical solution unless you have no oxygen.

Definitely the only practical solution in a non-pressurised aircraft, unless you are one of the canular O2 types. At low altitudes in a non-pressurised aircraft it is sometimes advisable to get to a lower altitude at night.

I found myself over the Outeniqua mountains at night and realised that something was going awry with my night vision at 10,000 feet and reduced my safety margin by descending to 8000 feet and found my night vision improved considerably. A very mild form of hypoxia, but along with fatigue, even mild hypoxia can affect those that skulk well below FL 350!

[Fox3WheresMyBanana]

We used to use a similar situation at the Arizona pilot training school I worked at- the Chief Pilot was also ex-RAF. We'd do a night navex to Vegas, and plan one leg where we would climb up to 12,000 for a time, and the students would notice within 10 minutes that their night vision had decreased. There was then some sums to do to calculate a position from beacon radials. Then we'd go back down to 10,000 and repeat,then 8,000. Very good way of proving the point.

[PHXPhlyer]

Single pilot operations above FL 250 or so is asking for it, I think.

Oxygen requirements for this flight:

§ 91.211 Supplemental oxygen.

(a) General. No person may operate a civil aircraft of U.S. registry—

(1) At cabin pressure altitudes above 12,500 feet (MSL) up to and including 14,000 feet (MSL) unless the required minimum flight crew is provided with and uses supplemental oxygen for that part of the flight at those altitudes that is of more than 30 minutes duration;

(2) At cabin pressure altitudes above 14,000 feet (MSL) unless the required minimum flight crew is provided with and uses supplemental oxygen during the entire flight time at those altitudes; and

(3) At cabin pressure altitudes above 15,000 feet (MSL) unless each occupant of the aircraft is provided with supplemental oxygen.

(b) Pressurized cabin aircraft.

(1) No person may operate a civil aircraft of U.S. registry with a pressurized cabin—

(i) At flight altitudes above flight level 250 unless at least a 10-minute supply of supplemental oxygen, in addition to any oxygen required to satisfy paragraph (a) of this section, is available for each occupant of the aircraft for use in the event that a descent is necessitated by loss of cabin pressurization; and

(ii) At flight altitudes above flight level 350 unless one pilot at the controls of the airplane is wearing and using an oxygen mask that is secured and sealed and that either supplies oxygen at all times or automatically supplies oxygen whenever the cabin pressure altitude of the airplane exceeds 14,000 feet (MSL), except that the one pilot need not wear and use an oxygen mask while at or below flight level 410 if there are two pilots at the controls and each pilot has a quick-donning type of oxygen mask that can be placed on the face with one hand from the ready position within 5 seconds, supplying oxygen and properly secured and sealed.

(2) Notwithstanding paragraph (b)(1)(ii) of this section, if for any reason at any time it is necessary for one pilot to leave the controls of the aircraft when operating at flight altitudes above flight level 350, the remaining pilot at the controls shall put on and use an oxygen mask until the other pilot has returned to that crewmember's station.

Oxygen requirements for Air Carrier:

§ 121.333 Supplemental oxygen for emergency descent and for first aid; turbine engine powered airplanes with pressurized cabins.

(a) General. When operating a turbine engine powered airplane with a pressurized cabin, the certificate holder shall furnish oxygen and dispensing equipment to comply with paragraphs (b) through (e) of this section in the event of cabin pressurization failure.

(b) Crewmembers. When operating at flight altitudes above 10,000 feet, the certificate holder shall supply enough oxygen to comply with § 121.329, but not less than a two-hour supply for each flight crewmember on flight deck duty. The required two hours supply is that quantity of oxygen necessary for a constant rate of descent from the airplane's maximum certificated operating altitude to 10,000 feet in ten minutes and followed by 110 minutes at 10,000 feet. The oxygen required in the event of cabin pressurization failure by § 121.337 may be included in determining the supply required for flight crewmembers on flight deck duty.

(c) Use of oxygen masks by flight crewmembers.

(1) When operating at flight altitudes above flight level 250, each flight crewmember on flight deck duty must be provided with an oxygen mask so designed that it can be rapidly placed on his face from its ready position, properly secured, sealed, and supplying oxygen upon demand; and so designed that after being placed on the face it does not prevent immediate communication between the flight crewmember and other crewmembers over the airplane intercommunication system. When it is not being used at flight altitudes above flight level 250, the oxygen mask must be kept in condition for ready use and located so as to be within the immediate reach of the flight crewmember while at his duty station.

(2) When operating at flight altitudes above flight level 250, one pilot at the controls of the airplane shall at all times wear and use an oxygen mask secured, sealed, and supplying oxygen, in accordance with the following:

(i) The one pilot need not wear and use an oxygen mask at or below the following flight levels if each flight crewmember on flight deck duty has a quick-donning type of oxygen mask that the certificate holder has shown can be placed on the face from its ready position, properly secured, sealed, and supplying oxygen upon demand, with one hand and within five seconds:

(A) For airplanes having a passenger seat configuration of more than 30 seats, excluding any required crewmember seat, or a payload capacity of more than 7,500 pounds, at or below flight level 410.

(B) For airplanes having a passenger seat configuration of less than 31 seats, excluding any required crewmember seat, and a payload capacity of 7,500 pounds or less, at or below flight level 350.

(ii) Whenever a quick-donning type of oxygen mask is to be used under this section, the certificate holder shall also show that the mask can be put on without disturbing eye glasses and without delaying the flight crewmember from proceeding with his assigned emergency duties. The oxygen mask after being put on must not prevent immediate communication between the flight crewmember and other crewmembers over the airplane intercommunication system.

(3) Notwithstanding paragraph (c)(2) of this section, if for any reason at any time it is necessary for one pilot to leave his station at the controls of the airplane when operating at flight altitudes above flight level 410, the remaining pilot at the controls shall put on and use his oxygen mask until the other pilot has returned to his duty station.
IIRC my company required use if above FL 250

(4) Before the takeoff of a flight, each flight crewmember shall personally preflight his oxygen equipment to insure that the oxygen mask is functioning, fitted properly, and connected to appropriate supply terminals, and that the oxygen supply and pressure are adequate for use.

PP

[Ex-Ascot]

If the pilot had a heart attack I would think that someone from the cabin would have gone onto the flight deck when they did a 180. If not then when they had fighters on their wing tips. Probably not able to fly the thing but at least make a radio call.

[Ex-Ascot]

From this passenger list, who would you select as being competent and calm enough to attempt such a task?

“John Rumpel’s daughter, a 2-year-old granddaughter and her nanny were onboard the plane,”

Either of the ladies. The 2 yr old would be needed to program the nav computer. It doesn't matter what old frequency he was on there would almost certainly be someone airborne and within range to hear. The F-16 pilots do not report of anyone waving from the cabin. Also the flight deck on the Cessna 560 Citation V can be seen from the cabin. A slumped over pilot would have been noticed.

[admin2]

Some of the posts relating to BM's posts about Corona virus have been relocated to a new thread at viewtopic.php?f=7&t=7993 at his request.

[OneHungLow]

Some of the posts relating to BM's posts about Corona virus have been relocated to a new thread at viewtopic.php?f=7&t=7993 at his request.

I suppose this isn't the moment to posit my "pilot alien abduction theory" ref. this accident!

[Ex-Ascot]

Go ahead OHL. Anyway here is a new analysis. Love the bit where the pilot says he has visual with the F-16 observed in a vertical climb. He should have added 'I wish that I could do that'

[Ex-Ascot]

Two opposite opinions. I am going for the 1st guy. Note the pilot was slumped to the right. In view of the pax.

[Boac]

Good looking chick! Personally, however, I likewise will ignore the rest of that video...........

I'm well out of date on modern FMC systems, but the ones I am familiar with would drop into 'last heading and altitude' mode in the scenario where an aircraft was unmonitored and 'ran out of route' as this would have done overhead destination. To then manoeuvre to apparently return to departure is weird.

Let's hope there is enough left for the medicals to establish the pilot's state of health at the time of the crash.

[Ex-Ascot]

My not so recent experience is that it would fly you to destination and put you in a hold.

[Boac]

How would it know where to hold? Was it in the programmed g/a route?

[Ex-Ascot]

Destination beacon.