Independent Group member Bill Holland appears to have sorted out the head-scratcher concerning the location of the QZ8501 tail section. His explanation jibes with where we’d expect the plane’s fuselage to wind up, given the fact that just before it disappeared from radar it was descending with alarming speed. I’m pasting here Bill’s recent email in toto:
I think I have the tail GPS coordinates figured out…
I kept finding references to the tail being found that translate as:
The mapping experts who are in MGS Ship Geo Survey finds it precisely in the coordinate 03.3839S (South latitude) and 109.4343E (East Longitude).But, I searched and found a version that seems to make more sense:
Aga pun menyampaikan titik koordinatnya, yakni: Latitude 3;38;39S, Longitude 109;43;43 E.
…in English:
Aga also convey the point coordinates, namely: Latitude 3; 38; 39s, Longitude 109; 43; 43 E.The numbers being quoted are correct, … Only the punctuation was wrong!
-03° 38′ 39″ 109° 43′ 43″ (degrees minutes seconds)
This is about 2.5nm South East of the last SSR/ADS-B location (Google Maps measures 3.03 statute miles = 2.63nm)In my screen grab [above]:
– the lower yellow start marke the tail section (and the blue annotation is the distance from the purple star)
– the purple circle is the last lat/lon from the SSR (ADS-B),
– the purple star is the approx location from the primary radar image.
– The red box is supposed to be “Most Probable Area 2”,
– the black tilted rectangular outline is the left (Western) section of the “Underwater Search Area”.
– The yellow diagonal line is Route M635 between TAVIP to RAFIS.
– The black diagonal line is the FR24 estimated flight path (the inverted teardrops are individual extrapolations from FR24 after the last valid ADS-B data data they received)[ignore the white square, the blue square, the Northern yellow star, and the green diagonal line]
-Bill
Really, it’s remarkable that searchers didn’t scour this location right away, and instead spent a week searching far down-current. There appears to have been some confusion between the nature of floating debris, which disperses as it’s carried by currents, and debris on the seabed, which will tend to remain where it falls, more or less directly under the point where it impacts the water.
The latest news is that preparations are underway to raise the tail section and hoist it onto a ship. Hopefully, the black boxes will be found within, and the cause of the accident one step closer to being revealed.
So glad to see this resolved. TNX Bill. Why only 3 ships there? All the big stuff will be on the bottom within ~2 miles even if it broke up at altitude…which is likely.
Jeff, Thanks for spreading the word.
The website that showed the latitude/longitude as three 2-digit numbers is
http://m.detik.com/news/read/2015/01/07/120203/2796208/10/objek-kubus-10-meter-letaknya-tak-jauh-dari-lokasi-lost-contact-terakhir?n991104466
I had suspected the formatting was the problem since all of the search grid coordinates were specified in degrees minutes seconds. It makes sense that the official location report would be in the same format.
-Bill
From 3 ships on day11 to 11 ships on day13.
Somebody needs to give the Indonesian search and rescue parties a hand. In other words, push them aside and let some competent parties take over. At this rate, there will be no bodies left to recover by the time they finally get their act together. How tragic for the loved ones of the victims.
http://www.wsj.com/articles/airasia-flight-8501-black-boxes-may-not-be-in-tail-section-1420787692
————-/
http://graphics.wsj.com/mh17-crash-map/
————-
Where were mh17 black boxes found ?were they still in tail? I can’t find a reliable explanation, but looking at some photos of when the rebels handed over mh 17 boxes ,they were in remarkabley good shape .not a scratch on them! There’s hope for 8501….
Well, a lot of other countries are pitching in. The US Navy, as far as I understand, has recovered about half the bodies found so far.
The debris field for MH17 was reported to cover 13 sq mi. That was the surface area littered for a catastrophic breakup at FL330, similar to the highest point of breakup possible for QZ8501. QZ8501 may have broken up slightly higher, or at a lower altitude, and possibly on the surface, but regardless of where it started braking up, this means the debris field was probably <13sq mi, or a 2 mile radius around the center of the impact area. The tail could be at the center, or on the edge of the field, so a very conservative assumption would be to look within a 4 mile radius of the tail. That estimate can be tuned (reduced) as more pieces are found in the area. But it is highly unlikely that any other heavy pieces will be found further than 2 miles from the center of the debris field.
I agree, since it is highly unlikely that, for example, an engine separated at FL 360.
Little has been discussed about the engines on QZ8501. The low speeds observed in the final minutes suggest that the engines were not running at normal thrust all the way to the ground. But when was the thrust reduced and why? Was there one or more engine failures, possibly due to hail ingestion or did the crew reduce thrust to bail out of the storm, or ??? Did they run out of fuel? Surely we would have heard about that by now. Was there an event at altitude that caused both engines to stop and left the crew incapacitated instantaneously (explosive decompression, etc.) resulting in a descent similar to what was observed in MH370 simulations (steep, turning descents with Phugoids)?
@victor, all
no connexion between MH17 and MH370 incidents found. see multimedia presentation here:
http://www.spiegel.de/panorama/gesellschaft/mh17-wer-hat-die-boeing-ueber-der-ukraine-abgeschossen-a-1011983.html
In a very careful investigation of the papers “Der Spiegel”, “correctiv” and “Algemeen Dagblad” the investigative journalist Cord Schnibben with a multinational team proved, that MH17 was taken down by a specific BUK-system operated by russian military to protect russian T62 tanks deployed in the region on ukrainian territory. Since the BUK system is not designed to discriminate between civilian and military targets and not designed for airspace surveillance but for very rapid random reaction to possible threats from the air (in this wargame every second counts heavily), it can be ruled out, that MH17 was specifically targeted by the russians and it can be ruled out, that it was shot down by another (ukrainian) airborne or groundbased system. So MH17 was eaten by the beast of war and certainly someone should go to the UN Court in the Hagues, but there is no connexion thinkable to any scenario for MH370.
Your assumptions about the engines are not correct @airlandseaman. Engines could be at MAX T.O. Power and depending on the aircraft’s angle of attack you would still get low airspeeds. FDRs will show the parameters, and I guess very similar to those of AF447, which impacted the seabed at less than 100kts of airspeed and engines at full power.
@CosmicAcademy, “there is no connexion thinkable to any scenario” linking MH17 to MH370? Have you not read my delightful series of blog posts, starting with “Occam’s Razor is Overrated”?
http://jeffwise.net/2014/12/01/occams-razor-is-overrated/
You may not agree with my Spoof scenario, you may indeed consider it ridiculous, but it is surely “thinkable.”
@Avioesemusicas: I agree. The lift-induced drag on the plane goes as the square of the angle of attack. It does not take a big increase in the AoA before there is a significant reduction in speed due to the limited thrust of the engine.
CosmicAcademy:
I haven’t gotten through the correctiv+ +DerSPIEGEL +ADnl MH17 presentation yet, but it’s very clear there are loads of unaddressed ‘irregularities’ in this investigation.
Here’s a big one:
https://twitter.com/nihonmama/status/542800400730972161
Victor and Avioesemusicas:
What I wrote was: “The low speeds observed in the final minutes suggest that the engines were not running at normal thrust all the way to the ground. “.
Please note all the qualifiers. I do not see any possibility that the engines were running at normal thrust at impact. The speeds are not consistent with scenario. Too much time wasted on AOA speculation. The airplane was apparently not even “flying” in the ordinary sense, with airflow over the wing in the normal direction, so the AOA concept does not apply in that case.
@airlandseaman: True. At some point there was probably a loss of thrust as evidenced by the extremely slow speeds at the last radar point.
Victor:
I’m not suggesting this happened, but to illustrate the point about the applicability of AOA analysis, the plane could have been in a tailslide (flying backwards) at 23:19:46 and you could not tell that from the GPS speed and rate of descent. FDR will tell us what happened.
Quote:
” I do not see any possibility that the engines were running at normal thrust at impact.”
If the airplane was at an AoA of 40 – 50 degrees (like AF447) the drag would be so high that thrust doesn’t make much difference.
Can somebody explain why the Indonesean radar data with regard to QZ8501 are considered as sufficiently accurate to draw a number of conclusions posted here, while the Malaysian and Thai data with regard to MH370 are considered as inaccurate and untrustable?
In addition to @Oleksandr post:
why would have Indonesian radar miss MH370 overflying its airspace ?
Oeksandr: There is ADS-B data available for QZ8501 until moments before impact. We only have SSR/ADS-B data for MH370 for the portion of the flight before the turn at around 17:26Z. After that, we only have the primary radar data made available by Malaysia, without knowing how that data was compiled, and without access to the raw data. It is like comparing apples and oranges.
I believe that figure 1 in Jeff Wise’s post “Why AirAsia 8501 Disappeared From Radar” is the last SSR data received from the A/C.
Figure 2 shows “Geo Altitude” and “ Geo vertical rate” while the “Baro” fields are blank. My interpretation is that the “Geo” data represent primary radar returns.
Victor,
Thanks. Re QZ8501. According to Wiki “The aircraft disappeared from radar at 06:17 and the ADS-B transponder signal was lost at 06:18 WIB. The last altitude recorded by Flightradar24 from the ADS-B transponder was 32,000 ft (9,750 m).” If there are no other data, statements of kind “engines were not running at normal thrust all the way to the ground” are at least premature in my opinion.
Btw, just a thought: what if the portion of the MH370 radar data after the gap around MEKAR is coming from the Indonesian radar in Lhokseumawe under Malaysian “Butterworth logo”? In other words, another explanation why the Indonesean military deny any detection of MH370 is that having data from around MEKAR to the point of the final disappearance, they simply did not want to publicly demonstrate capability/incapability of their air defense system over the Malacca Strait and Andaman Sea. Then the gap in the data could be explained by merging datasets from different radars. Implication: did turn at MEKAR really occur, or was it side effect of merging?
@Oleksandr: There is additional SSR/ADS-B data that was tweeted by @GerryS. At 23:19:46, the position was -3.613429,109.697349 (about 2.6 nm from the recovered tail), the geometric altitude was 24,025 ft, the RoD = -11,518.75 ft/min, the track was 197 deg, and the ground speed was 64.82 knots.
Don’t believe everything you read in Wikipedia.
Victor
WSJ: AirAsia Flight 8501: Official Says Black Boxes Likely Fell Out of Tail Section
Updated Jan. 9, 2015 7:19 p.m. ET
“air-safety experts said the condition of some victims’ bodies suggested the plane didn’t come apart in midair, and may have hit the water at a relatively shallow angle.”
http://t.co/60du2vlPIW
Continuing to read all QZ8501 dot-connecting with keen interest.
MH370 housekeeping: my Jan.7 6:53PM post (prior thread) re: computing range ATSB has removed since mid-March:
Two problems discovered upon review:
– I had inadvertently rotated 8°, not 6° as claimed (and intended).
– 6° corresponds to full-on cruising speed, so my range reduction estimate is more accurate if I test using faster paths
After thus correcting and refining, my revised estimate is now 7.4% of post-radar range. (Please disregard my initial 12% estimate, with apologies.)
This figure makes far more sense, because I had months ago deduced that 11% loss of range would leave the 7th arc unattainable altogether.
The revised graphic won’t be posted in my usual, slap-dash manner, however – it is being incorporated into a comprehensive document I hope to circulate for expert review very shortly.
Thanks.
VictorI:
Airplanes navigate on barometric altitude, the transponder reports barometric altitude, ATC uses barometric altitude for separation between airplanes, TCAS uses barometric altitude.
Who cares about geometric altitude?
@gysbreght: I supplied the last data that was received and leaked to the public, which included the geometric altitude but not the barometric altitude. Prior data that I am not at liberty to release included the barometric altitude. The geometric altitude was 2000 ft higher than the barometric.
@JeffWise
Link between MH17 and MH370
Sorry, you misunderstood my entry, which was addressed to victor, because he once suggested a scenario with a ukrainian revenge attack against malaysia for theft of gold in the cargo of MH370. I just wanted to alert victor there might be need to revisit that part of his narrative, after there is abundant evidence now of the russian responsibility for that attack.
As to your idea in the narrative about Occams razor you are completely right. MH17 was the event where everybody had to start a re-evaluation of the russian intent and attitude, namely after Putin consumed large chunks of a sovereign neighbour, dismissed all of his liberal or economic advisors and brought back his old boys network from former KGB as the body of power in the Kremlin.
The evolution of the deterioration of relationships with russia in hindsight makes your scenario much more plausible than it even was back in August, because now the russian leadership officially considers NATO as enemy and hostile force (and a target for all kind of operations being done back in the cold war).
So you can expect that the accompanying changes of rules of engagement were already in place at the time of the Crimea occupation, well around the capture of MH370. The west waited to see how serious this would be, but now, after even Gorbatschow warns of a devastating war in the heart of Europe, you can guess that the russians use ALL available means to prepare for that contingency.
The trademark of the old boys network in power in the Kremlin is, to use the forces they were trained for back in the seventies, when they were young. Mainly the use of proxies to test the west and keep the pot boiling. They had their advisors in a lot of arab and middle east countries as well as close ties to india and indonesia then. By that time they sponsored all sort of terror if it was only directed at NATO and the US (see e.g. the Carlos story). Now that they assess NATO no longer as a partner but as a unwanted hostile force at their borders, there is no longer cooperation in the war against (islamic) terror. To the contrary we find ourselves fallen back to the times were political assassinations, abductions (of scientists), hijackings of planes and all kind of dirty tricks were part of our everyday life.
Still the old networks exist and its highly likely, that from their old standard connexions to middle east and south east asian nations they might well be the force behind the raise of the caliphate in syria and iraque, since these disorganized and inept gangs suddenly got tactical and strategic capabilities that surprised us heavily. They might have opened pandoras box and use their old relationships for sponsorship of islamic terrorism.
This might well be what Putin was talking about, when he said that the sanctions will fall back on the west.
As a result we can assume that the plausibility for a russian involvement in the capture of MH370 (mainly through some terrorist or separatist proxy) is much greater than it was back in March 2014
VictorI:
My point is that geometric altitude is only used by the primary radar, and therefore primary radar is the source of the altitude in figure 2, and probably also in figure 1.
@VictorI:
“The geometric altitude was 2000 ft higher than the barometric.”
The difference between geometric and barometric altitudes varies with altitude when the temperature is off-standard.
@gysbreght: More precisely, I have been told that when the barometric altitude was 32000 ft, the geometric altitude was 34000 ft. I don’t agree with your statement that the leaked data must come from primary radar. The data is more likely SSR/ADS-B data, and the barometric altimeter was not working for the last data point.
@VictorI: If the barometric altimeter was not working, from what source was the geometric altitude generated. No system in the airplane simply replaces baro altitude with GPS altitude or radio altitude.
@gysbreght: I think you are mistaken. I simple Google search shows that A320s equipped with an Enhanced Ground Proximity Warning System (EGPWS) use GPS altitude as an input to determine geometric altitude. The accuracy of the calculation is improved if barometric altitude is available. However, if it is not, the GPS altitude can still be used to estimate geometric altitude.
Please see this white paper from Honeywell which provides additional details:
http://www51.honeywell.com/aero/common/documents/Geometric-Altitude-Paper.pdf
@gysbreght: Here is another white paper which discusses how geometric altitude and barometric data are integrated in the ADS-B data for ATC. Geometric altitude may be reported if barometric altitude is not available.
http://www.icao.int/APAC/Meetings/2012_SEA_BOB_ADSB_WG8/WP06_HKG%20AI.%205%20-%20Use%20of%20Barometric%20Altitude.pdf
I think we can be relatively certain that the last radar data that was leaked for QZ8501 was SSR/ADS-B data and not primary radar data. In fact, the format of the data in the screen shot exactly matches other ASTERIX screen shots available on the web.
@Victor I;
Thanks for linking two interesting papers, in particular the Hongkong paper presented at an ICAO Working Group meeting.
I have learned that the ADS-B data format provides both barometric Flight Level and geometric (GPS) altitude. The paper states that the GPS altitude is not used for ATC purposes but states also:
“Upon checking with major equipment suppliers providing ATM automation system, it is revealed that while all systems will process and display barometric altitude by default, some of them do process and display geometric altitude, without any alert/warnings to controllers, in the event that barometric altitude is absent.”
and also that States/Administrations are recommended to implement their ATM automaton system so that:
“(b) in the event that barometric altitude is absent, geometric altitude could be displayed for situational awareness purpose, but not for aircraft separation. Moreover, an appropriate sign should be indicated against the displayed attitude to duly alert controllers.”
So is the FL363 shown in figure 1 of Jeff’s post baro or geo?
Sounds like the black boxes are found
@gysbreght: The barometric altitude was available at the time of the radar screen image. The value 363 is indicative of FL363 barometric. The barometric altimeter was working at the time of the radar screen image in Fig 1 but not working at the time of the tabular values shown in Fig 2.
CosmicAcademy – I was at a gathering yesterday and noticed a couple of guys standing talking that I intended to catch up with. Both are professional. After standing alongside for a few moments it was obvious they were talking about MH370 and the agreed view was that nothing about it looks right and that there is plenty we don’t know. Even when I quiz people randomly this seems to be the case. It’s a rejected narrative out there.
@Victor I:
Thanks for clarifying these issues.
@sk999,
Thank you for identifying and localizing the error in my BFO model. I was interpolating the satellite velocity components between 18:25 and 19:41, and my Excel formula for the satellite Z component velocity was incorrectly entered. The shift I see after making the correction is about -10 Hz at 18:34 in delta_F (down), as you predicted. My BFO model predictions at other times (prior to 18:25 and after 19:41) are unaffected.
@VictorI,
@airlandseaman,
I am in the process of generalizing my BFO model in anticipation of trying to match the rather complex set of BTO and BFO values between 18:25 and 19:41. It is becoming more and more apparent to me that a complex maneuver must have occurred during this period of time. Initially, in order to make the problem tractable, I (and most others) assumed one major turn during this time. That allows route fits that match the 7 ATSB BTO arcs and the BFO data at those same epochs. However, I have been unable to find any single-turn route that matches all the reliable 18:27 to 18:40 BTO/BFO data, especially at 18:27 and 18:28, unless significant and variable climb rates are included. I can’t prove these did not occur, but I think it more likely that additional turns are the cause. Climbs alone can be used to match the BFO data, but they cannot explain the small change in BTO between 18:25 and 18:28. An early turn is required, probably to the North. Then a second turn south is needed to properly approach the 19:41 arc.
I have recently completed about 90 route fits covering the many combinations of the following parameters:
1. Altitude: 35,000 or 40,000 ft
2. Lateral navigation mode: True Track or Great Circle
3. Initial southward bearing: Variable or fixed (at values corresponding to Inmarsat and IG models)
4. Speed control mode: constant true air speed or Mach 0.84 or Long Range Cruise
5. Data fitting range: 18:22 to 00:19 or 19:41 to 00:19
As usual, I fit the BTO data (within the ATSB error bounds) subject to minimizing the RMS air speed variations with respect to the selected speed model. The matrix of NOAA temperature data was used to determine the air temperature at each point along the route for calculating the true air speed from the Mach number in the profile being fitted. I will publish the details of this work in a new addendum to my white paper.
I was particularly interested to see if any specific route (i.e., a very narrow range of bearings) could be fit to the 19:41 to 00:11 BTO arcs without any constraining connection to the path from 18:22 to 19:41.
In addition, I have calculated the performance limits for 9M-MRO starting with the known fuel on board at 17:07. I used a similar process to that previously performed by Victor Ianello. For Rolls Royce Trent 892 engines, a PDA of 1.5% yields fuel exhaustion at 00:16 with Long Range Cruise at a constant 35,000 ft altitude. With step climbs from 35,000 ft to 41,000 ft, Long Range Cruise mode is virtually identical to Mach 0.84 cruising, and a 2.2% PDA produces fuel exhaustion at 00:16. The Equivalent Still Air Distance (ESAD) from 17:07 to 00:16 is 3,454 NM at 35,000 ft and 3,548 NM with the step climb. For comparison purposes, I also calculated the same parameters for GE 90-94B engines. In this case I get 1.4% PDA for 00:16 fuel exhaustion in Long Range Cruise at 35,000 ft, and 3,466 NM ESAD. At 40,000 ft and the same other parameters, I get a 0.2% PDA and 3,565NM ESAD. The GE engine calculations take into account the higher fuel consumption and higher speed on the particular night in question. The fuel consumption table I have for the Rolls Royce engines does not specify the assumed standard temperatures, so I have not applied any corrections to those numbers. In general there is a slight penalty for operating at temperatures above standard conditions. On the night in question, the elevated temperatures cause fuel consumption to increase by about 4% while the speed increases by about 3%. Thus there is a net reduction in range of only about 1% in this case. I also note that the ranges I calculated for the GE engines agree within about ½% with the Rolls Royce ranges. This provides some confidence that the calculated ranges are fairly accurate.
For each route fit I calculated the total air miles traveled from 17:07 to 00:16 and then figured the PDA needed to match my calculated Rolls Royce engine ranges. Thus, for those route fits where the derived PDAs are reasonable values (perhaps about 1-3%), I have demonstrated that the route is flyable on the available fuel. For the cases where I fit only the 19:41 and later data, I assume the exact speed profile is flown between 18:22 and 19:41 to figure the air miles covered during this period.
Here is a preliminary summary of some of my findings:
With a single major turn assumption:
1. The best-fit speed profile is < 1 knot RMS and is a Great Circle route with either constant TAS or Mach 0.84. Both speed modes fit very well and have PDAs of about 2%.
2. True Track navigation produces speed errors (for all three speed modes) outside the bound I consider acceptable for the correct route (< 2 knots RMS).
3. Long Range Cruise at constant altitude is a very poor speed fit with both Great Circles and True Tracks.
With no turn assumption and data fitting starting at 19:41:
1. The ranges of bearings providing acceptable speed fits for Great Circle routes are 187-192 degrees for constant TAS and for Mach 0.84 (and its equivalent of Long Range Cruise with a step climb).
2. The range of bearings for acceptable speed fits with True Tracks is 183-192 degrees for constant TAS only.
3. If one assumes a constant TAS, either Great Circles or True Tracks fit well.
4. For Mach 0.84 speed control (including LRC with step climbs), only Great Circles fit well.
5. For Long Range Cruise at constant altitude, neither Great Circles nor True Tracks fit well.
6. The fits are insensitive to exact altitude, with no obvious preference for 35,000 or 40,000 ft.
7. The fact that the handshake arcs are nearly concentric means that there is a very high degree of rotational symmetry. This explains why none of the fits to the 19:41 to 00:11 arcs is narrow in angular range of acceptability. Instead, the bearings from these fits produce fairly broad bands of 5-10 degrees width. Some other constraint is required to define a unique path. This could be a waypoint, an independently known bearing, or a precise final turn time. I will continue to explore possible 18:22 to 19:41 routes that fit all the reliable BTO and BFO data to see if those data might constrain the 19:41 location sufficiently to precisely determine the southward bearing. If this is the case, then perhaps it is possible to identify a precise 7th arc position. Absent this constraint, the only other possibility I can see is to make a lucky guess of bearing or waypoint that also provides a good fit to an air speed profile.
Two findings of my parametric study surprised me: (1) There are no routes that fit Long Range Cruise well at constant altitude, and (2) there are no True Track routes that fit Mach 0.84 well. The only acceptable routes appear to be Great Circle (either constant TAS or Mach 0.84) or True Track (constant TAS).
I suspect that Mach 0.84 (or its equivalent of Long Range Cruise with a step climb) is a more likely speed control mode than constant TAS, but then I am left only with a Great Circle route. For this to be correct, then one of two things must be true. Either the notion that the FMS reverts to a True Track mode after passing the last entered waypoint is wrong (and the FMS in fact maintains the same Great Circle), or an unidentified waypoint south of ~40S latitude was used.
Bobby: How did the 90 trials compare to your earlier end point estimates?
Mike, did you use waypoints in your simulation, and if so, did the FMS revert to True Track after reaching the last one?
8501 FDR recovered.
PN-2100-4043-02
serial number SN-000 556 583
data sheet here:
http://www.l-3ar.com/PDF_Files/MKT001.pdf
Bruce: Our simulations did not attempt to resolve any pre flameout path questions. No WPs were needed for those simulations.
@ Dr. Bobby
Actually, no one really cares.
@airlandseaman,
Mike,
The end points range of acceptable routes vary from 83.7E to 91.5E. The western end of this range is my original end point. The eastern end is in between Richard Godfrey’s V13.1 and Victor Ianello’s 180 degree routes.
What I found is that in order to precisely match a speed model, one cannot fix a precise bearing without an additional constraint besides the BTO data. That constraint must also be something other than the BFO data. Victor assumed a waypoint and a 180 degree bearing. Inmarsat assumed a 180 degree bearing. I assumed a single turn scenario that lead me to a path that happens to pass through a waypoint. Richard’s route appears to me to be a compromise between matching BFO data and having a reasonably smooth speed profile. One of these could turn out to be correct, but I don’t see any way now to demonstrate uniqueness, with the possible exception of a full match to all of the BTO/BFO data from 18:25 to 18:40 (and even that could turn out not to be unique).
@DennisW ~ Posted January 11, 2015 at 11:11 PM ~ “Actually, no one really cares.”
• Incorrect, I care.
@Dr. Bobby Ulich
• Is the PDA the same for the RR Trent 892 as the 892B-17 engines installed on 9M-MRO?
~LG~
Bobby,
“The end points range of acceptable routes vary from 83.7E to 91.5E”. Nope. This is only valid under AP assumption, and including 18:40 BFO. I think I’m getting close to AT+TOGA scenario persistently ending not far from the “Chinese Ping” location. An important thing I carried out from the discussions with Gysbreght is the realization of the fact that the incorporation a proper fuel consumption model is essential. AT+TOGA makes a lot more sense compared to AP theory.
Does anybody here know dependence of fuel consumption rate on the thrust, mach, ambient air pressure and temperature specifically for 892B-17 or Trent 892 engines? I’ve just incorporated the dependence from El-Sayed A.F. “Aircraft Propulsion and Gas Turbine Engines”, but it is rather generic.