02-19-2016, 12:46 AM
(This post was last modified: 02-19-2016, 01:33 PM by ventus45.
Edit Reason: Edit tables
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Quote:slats11
Quote:Quote:Ventus45
He "must" therefore remain "in the dark" to avoid visual detection by ships or aircraft AND for him to be able to see the lights of ships, if any, because he doesn't want to ditch anywhere near one for obvious reasons.
For that and other reason, (many others), he "must" "overfly" his "intended ditch zone" in the dark, with him also "still in the dark".
He absolutely MUST remain in the dark, west of the terminator, until the last moments.
I used to think that Ventus. I think it was I who suggested this scenario and the terminator to you many months ago.
I agree we did discuss the terminator long ago, and we both had the same general idea at that time.
Since then, I have refined my thinking on the matter, apparently you have changed your mind.
I have concluded, that from a "mission planning perspective" that it is essential to remain in the dark, at all times.
See below.
Quote:Slats11
The hardest time to see any shipping (which I believe would have been a consideration) is when the sea is dark but you are in bright sunlight above. It is easier either in complete light (surface illuminated) or complete darkness (eyes adjusted to dark, and ships should have running lights on).
We are not "in the light" above a "dark sea".
Nor is there a choice of being in an "all dark" or an "all light" regime.
"Half-Half" is not an option.
And "all light" is not an option either.
It has to be "all dark".
It is not just about us being able to see a ship or a yacht without lights, it is all about us not being seen by someone else !!
We need to be in the dark, for three reasons:-
(1) with "dark adapted vision", to be able to see any lights on a dark sea, and
(2) to not be seen !!
(3) it is "necessary to overfly and "clear" the intended ditching zone in "the dark"
Quote:Slats11
If you want to ditch with sunlight at the surface, you would have been in sunlight at TOD.
No Slats, I beleive you have got that totally wrong.
Slats, my entire flight until below 2,000 feet is in the dark.
TOD is at 82E 37S, at FL400, (40,000 feet) at 23:40/41 zulu.
TOD is in the dark, at the bare beginning of twilight at that altitude.
Actual sunrise at TOD at FL400 is 23/24 minutes later, at 00:04 zulu.
Sunrise at TOD (82E 37S)
Alitude Time
Metres Feet FL UTC
12,200 40,000 400 00:04
11,000 36,000 360 00:05
10,100 33,000 330 00:06
9,000 29,500 295 00:07
8,000 26,240 262 00:08
7,000 23,000 230 00:09
6,000 19,680 197 00:10
5,000 16,400 164 00:11
4,000 13,120 131 00:12
3,000 9,840 098 00:14
2,000 6,560 066 00:16
1,000 3,280 033 00:18
600 2,000 020 00:19
500 1,640 016 00:20
200 650 006 00:21
100 328 003 00:22
30 100 001 00:23
0 0 000 00:24
BOD is at 82.8E 38.7S, at FL020, at 00:00/01 zulu.
BOD is in the dark, in the beginning of twilight at that altitude.
Actual sunrise at BOD at FL020 is 14/15 minutes later, at 00:15 zulu.
Sunrise at BOD (82.8E 38.7S)
Alitude Time
Metres Feet FL UTC
12,200 40,000 400 23:59
11,000 36,000 360 00:00
10,100 33,000 330 00:01
9,000 29,500 295 00:02
8,000 26,240 262 00:03
7,000 23,000 230 00:04
6,000 19,680 197 00:05
5,000 16,400 164 00:06
4,000 13,120 131 00:08
3,000 9,840 098 00:09
2,000 6,560 066 00:11
1,000 3,280 033 00:13
600 2,000 020 00:15
500 1,640 016 00:15
300 1,000 010 00:16
100 328 003 00:17
30 100 001 00:18
0 0 000 00:19
Thus, the entire descent track (green segment) is flown "in the dark", at the beginning of twilight.
In other words, he is descending "just under the lightening of the sky", all the way down.
Quote:Slats11
To minimise risk of not seeing a ship, you would want the surface illuminated.
In a perfect world, yes, but it is not possible to do that on this mission.
To be within visual range of a surface object in the light, we would also be in light and within visual range for them too.
In fact, it is more likely that a sailor on a yacht would see a 777 before we would see the yacht.
How about being so dead unlucky enough to have a submarine at periscope depth with some eagle eyed young Leut Navigator Officer, on the search periscope, in high power magnification, scanning the stars and the sea, around the full hemisphere, getting his eyes "dark adapted", whilst getting ready to do his "dawn sights" (as he is still "required" to do) to check, and if necessay, update the wonderful wizz-bang ring laser gyro inertial navigation systems etc ?
After taking his "sights" he retires to the plotting table and does the sums.
Whilst he is not looking, the captain pops up the gps antenna up, just to get a "second opinion" you understand !!
( Before you disolve in fits of laughter, be advised, they still do it slats ).
Where was I.
Oh yes.
Catch-22.
Do you now see why it is "necessary to overfly and "clear" the intended ditching zone in "the dark" ?
Quote:slats11
So on balance I now think likely east of the terminator - with a bit of "time" to spare in case fuel ran out early and the terminator was further east.
No slats, I do not agree.
As I indicated a couple of posts back, if either fuel issues reduced range or speed but NOT endurance, it would be the same as being "late", ie, you would be at a higher latitude, but still flying more or less parallel to the terminator, and the effective result would be the same.
On the other hand, less endurance is a factor that could force you east, but only a little, during the flight south.
Let's assume worst case.
Say we had lost an engine failure, and to really drop ourselfves in the deepest of all doo-doo, we also have a fuel transfer issue which prevents us using all the fuel in the live engine.
So we are flying lower and slower, and we have say 2 hours less endurance, ie, we only have useable fuel to last to say 22:19 instead of 00:19. Range from failure point would be a little over 60% of range without failures.
That would be a crisis.
We would be looking at the 22:00 terminator at about 20 south, which would be at 120 East.
That puts us on the West Australian coast !
If this drama occured at or before about 5 degrees south, we could just make it to, land and at, Port Headland, taxi to a bay, and simply say Hi !!
That would be "mission fail".
Get arrested, etc.
If our system issues occured any time after 5 degrees south, the only options would be turning for Cocos up to about 20 degrees south, after that, there is no option, we are in the water, in the dark.
The point of all this is to demonstrate that since the mission objective is to "vanish", if you had a situation where your endurance was significantly reduced, you could not get far enough east quickly enough to meet the terminator. We are in the water, in the dark. A dark ditching is unlikely to be successful, it will almost certainly be a crash with lots of floating debris.
Besides, going east of 90E is not an option anyway, because it would put us within range of JORN.
Again, any outcome that fails to "vanish" is a "mission fail".
Quote:slats11
Your scenario suggests ditching didn't follow fuel exhaustion - which is obviously possible.
Correct.
It is obviously necessay to have power for the low level maneouvering, and desireable up to "the cut" at Vref + 40 at 100 feet (not 50 feet) at the beginning of the "hangar landing profile", which entails stabilising in ground effect as low as possible (need our shadow) to play the "energy management game", by both bleeding the speed off whilst minimising the vertical velocity in the last 10 seconds or so prior to the "alighting" on the water, just like a good old Sunderland or Sandringham or Catalina.
Quote:slats11
The best interpretation of the last ping however is that this was due to fuel exhaustion.
So "they" say. I am not convinced. As I have said previously, the APU auto starts when the Trents drown, etc. See previous posts.
Quote:slats11
All this is conjecture. Interesting. But conjecture none-the-less.
Of course it is. But I think it is far more interesting than most of the other stuff out there. Perhaps I am biased.
Quote:slats11
As it appears we are being prepared for an unsuccessful search, I am interested in the satellite sightings of what presumably appeared to be a cluster of debris further south and east. If it wasn't thought to be a cluster of debris, it wouldn't have been news at the time.
The "public" are being prepared for an unsuccessful search, "we" have no need to be "prepared", we already know. The "end-game" is the end-game. They are just going through the motions now.
As for those southern debris sightings, I really do think they come under the heading of "wishful thinking" by most people. I do not beleive they were MH-370 debris.
Quote:slats11
I am also intrigued at ATSB finally hinting at a possible controlled glide at the end. They were always fixated on the idea of an uncontrolled dive - presumably because it wasn't politically acceptable to draw attention to the inevitable implications of a controlled glide.
Beaker will now hint at anything, anything at all, that might fly, in a forlorn attempt, to try and save himself, from the inevitable bout of, rectus-pineapulus.
Quote:slats11
But now a controlled glide is at least being considered, I wonder if it ties in with these satellite sightings.
I doubt it.