Posted on 03/25/2014 7:17:19 PM PDT by Uncle Chip
I saw where the two possible routes that Inmarsat drew up assumed two different speeds south — one at 417mph and the other at 518mph. That’s quite a difference.
She should be along with the girlfriend who is probably the mystery woman who made the illegal call to him just before the flight.
“There is evidence of a partial handshake between the aircraft and ground station at 00:19 GMT,” said Hishammuddin Hussein, the acting transport minister. “This transmission is not understood and is subject to further ongoing work.”
Those Muzzies love the number 19!
Most of us pilots in my sphere of influence do not believe there was any climbing and certainly no rapid descent. It would not have served any purpose unless there was a struggle involved. Remember the transponder is off and Malaysian military radar can not accurately know for certain altitude from the distance all this was suppose to occur.
I agree there is no obvious need for climbing to 45,000 feet, or for a rapid descent (and no it couldn't have been 40,000 ft/min as reported), though I can think of a few possible reasons. Distracting the passengers and flight attendants, making them think maneuvering is in progress in the front so take your seats and strap in, avoiding a sighting from another aircraft, confounding military radar operators trying to plot a course, among others. But certainly it was not needed to kill the flight attendants and passengers. Manual pressurization could have taken care of that, much more quickly and effortlessly.
We have to accept as fact what the Malaysians (confirmed by the Thai's) said about the flight path. True, the altitudes aren't necessarily accurate but military air defense radars are designed to detect altitudes too -- unlike civilian (primary) radars. Think about it -- if you are about to direct an intercept you need an altitude. The altitude (and to some extent the speed) could tell you a lot about what kind of threat it is, and what its intentions are. You direct the interceptor to the target, and the interceptor locks on with its own radar when it gets close. But you need more information on the target than 'surface to 45,000', of course.
I don't know exactly what kink of AD radar the Malaysians have, but someone posted a link to an article about ours (entire US coastline), and it definitely can discriminate altitudes.
417 knots true airspeed (even assuming knots not MPH, is pretty slow for an airliner at altitude (assuming high altitude and light winds), but I think both speeds are achievable, depending on the altitude. At 35,000 feet the speed of sound is about 573 knots. So 417 knots true airspeed is about .73 mach, a not-unlikely fuel savings cruise speed, and 518 true airspeed is about .9 mach, which is very fast for a 777, maybe even a few knots out of range at 35,000 feet. But at 40,000 feet mach 1.0 is about 598 knots, so that would be about .87 mach, which is likely achievable by the 777 without an overspeed. I think those airspeeds are realistic, depending on the altitude.
And the humorous or sad part depending on ones point of view, Malaysia claims of altitude over land has been a moving target. Reports of 5,000 to whatever. One thing i am very certain of, it was never less than 13,000 feet. And what i do know, most likely higher. And as far as routing, Thailand ATC is only acknowledging the airplane's path south near the border of Malaysia and Thailand. Saying it never ventured into Thai airspace. They are quiet on any turns toward Phuket and the Andaman Sea. So even the announced flight path is brought into question.
The handshakes from the satellite gave it two options, the northern route would have taken it over northern Thailand. We know for certain that did not occur. It never entered Thai airspace.
Yes, of course. Tactical radars (not saying these were) have a high pulse repetition frequency, which limits their range since the reflections don't return before the next pulse is transmitted, but within their range they are very accurate. We don't know the exact capabilities of the radar used to track MH370, and they probably wouldn't share it publicly anyway. I don't blame them.
True for some aircraft, but not true under normal circumstances for a 777. The 777 has TAC (thrust asymmetry compensation).
Thrust Asymmetry Compensation The thrust asymmetry compensation (TAC) system significantly reduces uncommanded flight path changes associated with an engine failure. TAC continually monitors engine data to determine the thrust level from each engine. If the thrust level on one engine differs by 10 percent or more from the other engine, TAC automatically adds rudder to minimize yaw. When TAC is operating, the pilot can still recognize the initial onset of an engine failure through airplane roll/yaw cues. These roll/yaw cues are greatly reduced when compared to an airplane operating without TAC. After several seconds, TAC applies sufficient rudder to make it possible for the pilot or autopilot to center the control wheel....[www.smartcockpit.com]
After the second engine flameout, the autopilot would drop off line, as would the last generator.
Right. That's not the part I was thinking of -- it doesn't turn off ADS-C ("contract", I know I said ADS-B, not the same), assuming it was in use (maybe not, it was a short overwater segment). Yes, I think turning off the ACARS (or disabling its communications) could be accomplished without pulling circuit breakers. I'm sure he had all this thought out beforehand -- except disabling the SATCOM. He screwed up that part.
Not sure what you mean by that. It's a chemical generator, not dependent on pressure altitude as far as I know. When the chemical reaction is over, no more oxygen.
If it were liquid oxygen supplying the masks (an option on the 777, but I don't think MH had this) then the oxygen for the passengers lasts longer with higher altitude (assuming they can stay alive with the lower partial pressures).
I don't think the pax lasted more than 30 minutes. The flight attendants probably a lot longer on the walkaround bottle -- but not for 7 or 8 hours!
Like you i have no idea what one has to do with the other and its the first I had heard or read that. Am sure it was talked about in class at some point, but again the brain does not think in those terms. I am going to be getting the hell down.
You mention no flight attendant could last 7 or 8 hours. Which now i am giving more thought. Actually yes it could happen. Let me try and explain. In the best case scenario, as you say no passengers lasts for more than 30 minutes. One, possibly two cabin crewmembers get on an portable oxygen bottle (as in the Helios 522 accident) which dependent upon flow lasts from 30 minutes to 1 hour.
Here is the kicker . . . The oxgen bottle in the cockpit only lasts 30 minutes. Or thats what we plan on. Of course many factors determine the exact amount. Probably longer. But by regulations at least 30 minutes.
Of course, if one really wants to play the game, one could say the pilot himself could have gained access to a portable oxygen bottle and last longer.
So since we are playing the theory game, it is conceivable a cabin crew member on a portable oxygen bottle can last as long if not longer than the cockpit crew. IF the pilot removed oxygen from the plane to kill the passengers, he himself only has 30 minutes of oxygen. So at some point if he wanted to remain alive, he would have to re introduce oxygen back into the plane.
IF he re introduces oxygen back into the system, any surviving crewmembers on the portable oxygen bottle could survive for the duration of the flight.
If he chose to kill himself also by not re introducing the oxygen and just let the plane fly forward, a surviving cabin crewmember could have gained access to the cockpit as the young man did in the Helios 522 crash, but not know what to do. And you are correct, run out of oxygen at some point.
In the Helios crash, they found all the portable oxygen bottles had been emptied. So at least more than one cabin crewmember got to them. I figured the surviving cabib crewmember used two bottles for himself to last as long as he did.
Here is the kicker . . . The oxgen bottle in the cockpit only lasts 30 minutes. Or thats what we plan on. Of course many factors determine the exact amount. Probably longer. But by regulations at least 30 minutes.
There were 12 crew on board, so minus the two pilots there were a minimum of 10 portable oxygen bottles on board. So theoretically if one flight attendant had all ten bottles in the back, then they might have survived for a long time, provided it wasn't too cold and the cabin didn't go much above 25k. But even if one or more of them survived, they can't gain cockpit access as long as someone is alive in the cockpit.
Of course, if one really wants to play the game, one could say the pilot himself could have gained access to a portable oxygen bottle and last longer.
So since we are playing the theory game, it is conceivable a cabin crew member on a portable oxygen bottle can last as long if not longer than the cockpit crew. IF the pilot removed oxygen from the plane to kill the passengers, he himself only has 30 minutes of oxygen. So at some point if he wanted to remain alive, he would have to re introduce oxygen back into the plane.
IF he re introduces oxygen back into the system, any surviving crewmembers on the portable oxygen bottle could survive for the duration of the flight.
If he chose to kill himself also by not re introducing the oxygen and just let the plane fly forward, a surviving cabin crewmember could have gained access to the cockpit as the young man did in the Helios 522 crash, but not know what to do. And you are correct, run out of oxygen at some point.
In the Helios crash, they found all the portable oxygen bottles had been emptied. So at least more than one cabin crewmember got to them. I figured the surviving cabib crewmember used two bottles for himself to last as long as he did.
The POB's can't be recharged, so once they are gone the flight attendants have no other options unless they can get into the cockpit. But there were at least 10 in the rear cabin (12 crew total on the aircraft, so 10 were in the rear cabin). So, supposing 30 minutes each bottle, or 2/hour (and that's optimistic), one flight attendant could last at least five hours, presuming they had all of the bottles unused, and they could survive the cold when the rear cabin was raised.
The pilots are on a liquid oxygen system, with at least two separate POB's. This oxygen system is completely independent of the system in the back. They have plenty of oxygen for the entire flight (more if there's only one alive in the cockpit). Oxygen availability isn't a limiting factor for the cockpit crewmember(s), unless they leave the cockpit, in which case they must first lower the cabin, or use a POB.
In the Helios crash there was nobody conscious in the cockpit to prevent entry. If the person in the cockpit of MH370 were conscious, they could have prevented any flight attendant(s) from gaining access indefinitely. If there was nobody conscious in the cockpit, a flight attendant could have gained entry, like with the Helios incident, but then of course they'd be in the same situation as the flight attendant was in that case, up a creek without a paddle.
First of all, "liquid oxygen" is NOT an option. Chemical oxygen (most likely, most common) or Gaseous Oxygen (not likely, due to weight and maintenance considerations)
Secondly. Yes, the cockpit oxygen separate from the passengers, however those Bottle(s) (gaseous) are located IN the E and E compartment. NOT the cockpit. Regulatory requirements are for 30 minutes per flight crew member and any jumpseater on deck.
So theoretically, it could be expected a single individual ONLY using cockpit crew oxygen can last ONLY for 90 to 100 minutes or maybe a little bit more.
Boeing does NOT list portable oxygen bottles in the cockpit as part of their emergency equipment. Most likely portable oxygen bottles NOT in the cockpit. However, I will give that a local (Malaysia) regulatory agency "might" require a single bottle, but not likely.
Exactly how many portable oxygen bottles in the cabin, of course would be known to the airline. For our purposes, Boeing lists only 4 with an additional 15 more as an option.
I will try one more time. A single pilot on cockpit oxygen at best can last 100 to 120 minutes on cockpit oxygen. At 25,000 feet for that period of time, he is either dead OR he has turned the packs back on and is using cabin air. If he has kept the pack off, and a flight attendant gets to at least 1 bottle immediately, they can survive for 1 hour per bottle. Thus outlasting the cockpit crewmember.
I read somewhere that El Al has double cockpit doors.
Pilot needs to go, he exits the inner door first, and it's locked behind him, before he exits the outer door.
Or any other medical emergency that might befall the pilots.
Don't sell that autopilot short. It did way better than a thousand miles!
I hope you're not seriously suggesting the cockpit O2 is chemically generated, like the pax system. That's a non-starter.
I said "cockpit oxygen" meaning the O2 supply for the cockpit crewmembers, not that the ship's O2 system supply bottles (whether gas or liquid) had to literally be in the cockpit.
30 minutes O2 per crewmember? In a 777 certified for ETOPS? So what do they do when there's smoke or fumes and they're 3 hours from the nearest alternate? Hold their breath, or breath the smoke/fumes? Ditch?
Here is the kicker . . . The oxgen bottle in the cockpit only lasts 30 minutes. Or thats what we plan on. Of course many factors determine the exact amount. Probably longer. But by regulations at least 30 minutes.
These are US FARs, but it's a safe bet ETOPS certified MH 777's could at least meet the following requirements.
(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.
So we have a crewmember who is a murderer, committing suicide, or a terrorist cell showing a government and other cell members how to do. Interesting either way.
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