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"What would happen to a 777 if, attempted to fly the plane well beyond its 43,100 foot max service ceiling? "

Its very simple, it no longer have enough air flowing over the wings creating lift, and the airplane will stall. Stall is the industry term for when a plane is not developing enough lift.

With that much fuel on board and admittedly not a full payload of passengers, nonetheless, AND in this part of the world temperatures well above average, the airplane would have stalled immediately if not within 90 seconds, depending upon alot of conditions

What happens next, depends upon again, alot of conditions. The characteristics of a particular design of an airplane and immediate reaction of the pilots. A wing will dip, ( first wing to stall) nose will pitch forward)

Having not flown a 777, can not say with full certainty, but common to every airplane the autopilot will automatically disengage. Alot of crap is going on in that moment. None of it good. All bad

What a moronic suggestion by Nance. I can decompressurize an airplane at 35,000 feet and accomplish the same. Ok instead of 13 seconds, passengers might have 30 seconds. I forgot the exact time guidance.

In either case, oxygen masks drop. Giving passengers 15 minutes of oxygen. Again because i would never ever think about it, am pretty certain (99.9%) oxygen masks can NOT be disabled.

I should have finished the whole scenario

In this case, radar shows a climb to 45,000. At some point the airplane will stall due to not enough airflow over the wings. A wing dips and nose pitches forward

A "good" pilot can recover at that altitude within 2 to 3 thousand feet. In the simulator almost all pilots can recover before losing 10,000 feet. That would be considered a failure of this recovery.

According to the radar, it shows a loss of 25,000 feet. Soooooo alot of other crap is going on. But they apparently recover. Or Did they?

I have been involved in only two accident investigations. In both cases, we saw anomalies in the Air Traffic control radar data. Meaning it can have a burst of inaccurate data. But the whole body of information usually smoothes out the anomalies.

Did the altitude changes occur before the transponder was no longer working. Hmmmmm according to reports all is normal until the point that the transponder is no longer working.

If the altitude changes occurred AFTER the transponder was no longer working, they are all full of crap, because they would not know with any certainty altitude heights.

Engines do stall above their service ceiling. Then the aircraft goes into glide mode.

Here’s an example of Pinnacle Airlines flight 3701.
http://en.wikipedia.org/wiki/Pinnacle_Airlines_Flight_3701

The two pilots were exploring the performance limits of the empty CRJ-200 on the ferry flight. The pilots decided to test the limits of the CRJ, and join the “410 Club,” referring to pilots who pushed CRJs to their maximum approved altitude of Flight Level 410 (41,000 feet).

The accident sequence started when the pilots performed several non-standard maneuvers at 15,000 feet, including a pitch-up at 2.3g (23 m/s²) that induced a stall warning. They set the autopilot to climb at 500 ft/min to FL410. This exceeded the manufacturer’s recommended climb rate at altitudes above FL380. In the attempt to reach FL410, the plane was pulled up at over 1.2g, and the angle of attack became excessive to maintain climb rate in the thinner upper atmosphere. After reaching FL410, the plane was cruising at 150 knots (280 km/h), barely above stall speed, and had over-stressed the engines.

The anti-stall devices activated while they were at altitude, but the pilots overrode the automatic nose-down that would increase speed to prevent stall. After four overrides, both engines experienced flameout and shut down. The plane then stalled, and the pilots recovered from the stall at FL380 while still having no engines. At that altitude, there were six airports within reach for a forced landing. This led the pilots to pitch nose down in an attempt to restart the engines, which requires a dive sharp enough to attain the required 300 kt for a windmill restart to make the blades in the turbines windmill at 10% N2 (turbine rotational speed). The captain did not take the necessary steps to ensure that the first officer achieved the 300-knot or greater airspeed required for the windmill engine restart procedure and then did not demonstrate command authority by taking control of the airplane and accelerating it to at least 300 knots.

However, the turbine blades expanded contacting the honeycomb labyrinth seals allowing the metal to scrape on each other when the engine overheated with zero core rotation. When the engine is shutdown at altitude, the core begins to cool and the stator, including the static Interstage Static Seal (ISS), contracts at a faster rate than the adjacent rotating parts in both the radial and axial direction because of its faster thermal time constant. The relative rate of cooling of the stator and rotor results in an alignment of the rotating seal knife-edges aft of the normal operating groove in the static seal. If the clearances are tight enough and the relative cooling rates are right, contact can occur between the static and rotating seal elements. The resulting stiction can temporarily prevent the rotor from turning when only the force of ram air is applied to the core. Air Turbine Starter (ATS) torque has been shown adequate to overcome this restriction (NTSB Accident Information Brief Update for October 29, 2004.) Thus, when the engine cooled, the assembly did not match anymore and the blades could not rotate freely. The crew ended the descent when they had reached 230 kt but neither engine core (N2) ever indicated any rotation during the entire descent. Since they were too high for an APU start, the ram air turbine (known as an “Air Driven Generator” on Bombardier products) was deployed to power the aircraft, and the crew donned oxygen masks as the cabin slowly depressurized due to loss of pressurization air from the engines.

The crew glided for several minutes. The crew then tried to restart engines using the APU at 13,000 ft. This was again unsuccessful. They then declared to Air Traffic Control (ATC) that they had a single engine flameout. At this point they had four diversion airports available to them. After continuing unsuccessfully to attempt to restart both the left engine (two times) and the right engine (two times) for over 14 minutes, while utilizing the emergency restart procedure, much altitude was lost. Despite their four auxiliary power unit-assisted engine restart attempts, the pilots were unable to restart the engines because their cores had locked. Without core rotation, recovery from the double engine failure was not possible. It was after these unsuccessful attempts that they declared to ATC that they had in fact lost both engines.

Unable to reach the assigned diversion airport, Jefferson City Memorial Airport, they crashed six minutes later outside Jefferson City, Missouri, behind a row of houses (the 600 block of Hutton Lane — two-and-a-half miles short of the airport), and the plane caught fire. Both pilots were killed. There was some damage to houses and a garage, but no one on the ground was hurt.

In this wacky scenario, one must take into account the physiology of the human body at altitude. A decompressed airliner at 35000 feet would affect ALL on board, crew and passengers unless the 777 has a cockpit that is somehow sealed from the rest of the aircraft for which I am not aware. Also, the oxygen system on the flight deck, as well as the walkaround systems used by the cabin attendants, is much much more sophisticated than those plastic drop downs in the passenger cabin. Oxygen would be required once cabin pressure gets above about 15k. In aerospace physiology, a term used is “time of useful consciousness” or TUC....TUC at 35k without O2 is between 15 to 30 seconds, depending on the individual...even less in some, particularly after a rapid decompression. TUC above 40k is maybe 5 to 10 seconds. Above 40k, unpressurized cockpit, 100% oxygen must be administered under pressure through the mask, for the human body to remain functional. The higher you get above 40k unpressurized, the more the pressure is required in the mask, and you must have to forcefully exhale against that mask pressure to get the 02 into the blood in the lungs. These physiological facts are why most airline flight ceilings are in the mid 30s for almost all airline activity. Business aircraft are frequently above 40k, think Mr. Payne Stewart’s ill fated flight. IIRC, above 40k, one crewmember MUST be on oxygen at all times, I.E. MASK ON...in the Stewart incident, not sure those regs were being followed. Also, unless the MA crew had not been breathing 100% O2 since at least takeoff, aka prebreathing in aeromedical physiology, to rid the body of as much nitrogen as possible, a decompression, weather intentional or otherwise to those flight levels, aviator decompression sickness, or the “bends”, comes into play. Particularly if the flight were to continue at those altitudes unpressurized. That is one of the most primary physiological concerns following a decompression at those flight levels...and the need to get to a lower altitude without delay, not just for oxygen supply and TUC concerns, but to also get barometric pressure back on the human body, to keep nitrogen in solution, and not let N2 come out of solution and into bubble form...aka bends. Above 50k, a decompression would cause the human blood to basically “boil” from the lack of barometric pressure on the body as N2 comes out of solution. Thus the reasoning for pressure suits used in all military flights above 50k...U2, SR 71, shuttle etc... Aircraft decompression is usually one of three types. Insidious, a slow leak for instance, rapid decompression, a window or door “popping out”, and explosive decompression, usually caused by total destruction...think shuttle Columbia here, or possibly that Hawaiian airliner that survived the cabin top basically tearing away in flight.. Explosive means the air escaping the vessel, (aircraft) is faster than the speed of sound.