What Happened to Asiana Airlines Flight 214?

At about 11:28 a.m. PDT on July 6, Asiana Airlines flight 214 crashed at the approach end of runway 28L at San Francisco International Airport (KSFO). Less than 24 hours after the accident, it’s way too early to know what happened, but there are some signs that the aircraft was not flying a stabilized approach at any part of the approach to land, and ended up low and slow just before impact.   Below, I outline the data that’s available at this time, and why I think that’s a possibility. But first, a disclaimer: There’s not nearly enough data to determine the cause of the accident. The below is speculation, based on the data available to me, which is not even a few percent of the data that will be available to the NTSB. Most speculation this early in the process is wrong, precisely because so little data is available. So anything below that may appear to be stated as a fact is really a conjecture.

First, the conditions at KSFO were ideal. The METAR 32 minutes before the accident was

KSFO 061756Z 21006KT 10SM FEW016 18/10 A2982 RMK AO2 SLP097 T01780100 10183 20128 51005

That is, there was a 6 knot crosswind to runway 28L, with good visibility. The winds aloft were light, so wind shear doesn’t appear to be a factor. Twenty seven minutes after the accident, the METAR was

KSFO 061856Z 21007KT 170V240 10SM FEW016 18/10 A2982 RMK AO2 SLP098 T01830100

Still a light crosswind, but with more variable direction. However, given how light the winds were, this would not likely have had a big impact on the landing. So weather doesn’t appear to be a factor. Indeed, the weather was near perfect at the time of the landing.

There are reports that the ILS glideslope was unavailable, but that the PAPI (precision approach path indicator) for runway 28L was functional. There are some conflicting reports that the PAPI was unavailable as well.  Aircraft were making visual approaches to 28L and 28R.

Using radar data  from FlightAware, I plotted the altitude and airspeed of AAR214, as well as that of UAL852, another 777 which landed successfully only 10 minutes beforeAAR214. Both flights were long distance international flights (UAL852 originated at Heathrow, London), probably both full of people but without much fuel, so both aircraft would have had more or less the same weight on landing, and therefore the same reference approach speed, V_{\text{ref}}. It’s instructive to compare the landing profile of these two flights. The first plot below is the altitude vs. distance from the touchdown zone for both aircraft. UAL852 is in black, and AAR214 is in red.

Note that UAL852 is on a nearly constant 3.2 deg glideslope. The PAPI for 28L is nominally 2.85 deg, but because a 777 is a large aircraft with a large cockpit to wheel height, it would be typical to fly the approach a tad steeper than the standard glideslope.

On the other hand, AAR214 is 500 feet or so above the glideslope until about 4 nm out. At 3 nm out, the aircraft is quite high, on a 4.48 deg glideslope to the touchdown zone, or about 50% higher than it should have been. From that point, the aircraft descends rapidly, presumably to acquire the correct glideslope. At about 1.5 nm out, the aircraft crosses and then descends through the glideslope.

At the last reliable radar return, the aircraft is at 100 feet, 100 feet below glideslope. Note, however, that the radar returns are quantized to 100 feet, so the result may not be very accurate. Nevertheless, you can see that the descent rate on short final is very high, perhaps twice what would be expected for a stabilized approach.

It gets worse. The plot below is groundspeed for the two aircraft.

Because the winds are light and generally a crosswind, the speeds shown are probably within a few knots of the actual airspeed. Since we don’t know the weights of the aircraft, we don’t know what target approach speed (V_{\text{ref}}) was. However, you can see that starting about 6 nm from touchdown, UAL852 slows from about 190 knots to about 145 knots. A typical (V_{\text{ref}}) for a 777 loaded with passengers but not much fuel is about 145 knots, so that makes a lot of sense. So UAL852 flew a stabilized approach, on the glideslope from 12 nm out, and slowing to V_{\text{ref}} for full flaps about 3 nm (1 minute) out.

On the other hand, AAR214 was never on a stabilized approach. Until about 30 sec before touchdown, it was high and fast. Only 3 miles out, it’s 20 or 25 knots too fast, and 500 feet high. As a result, the pilot no doubt reduced power to intercept the glideslope from above. 1.5 nm out (nominally less than 40 sec from touchdown), he’s finally on glideslope and at V_{\text{ref}} , but with a high sink rate on low engine power. If he applied power at that point, the engines would take some time (a few seconds) to spool up, and he would further sink below glide slope, slow down, or both.

The situation can be appreciated more precisely (but more technically) by looking at the total energy of the aircraft, that is, the sum of the potential energy due to altitude plus the kinetic energy due to velocity. The total energy is given by

    \[E=m g h + \frac{1}{2}m v^2\]

where m is the mass of the aircraft, g is the acceleration due to gravity, h is the height of the aircraft, and V is the velocity. Because we don’t know the weight of the aircraft, it’s convenient to normalize the energy by mg, yielding the energy height

    \[h_E = h + \frac{v^2}{2g}\]

The plot below compares the energy height for the two aircraft:

Note that the energy of UAL852 decreases at a steady rate until about 6 nm out, where the rate of energy dissipation increases, because the aircraft is slowing. At about 3.5 nm out, the rate decreases, because the aircraft has hit its target approach speed and stops slowing down.

AAR214 has a much different trajectory. At about 3 nm out, the rate of energy dissipation increases a lot, because the aircraft is both too high and too fast. As a result, the power is reduced significantly, perhaps even to near idle, in order to simultaneously slow the aircraft and get it down to the glideslope. At about 1.5 nm out, it has about the right airspeed and altitude (and therefore energy), but the energy continues to decrease precipitously. If the pilot added enough power at this point, a safe landing might have been possible. But it takes several seconds for the engines to spool up, and the pilot may not have added enough power or done so early enough, so both the altitude and airspeed continue to decrease below their desired values. Indeed, at the last radar return, AAR214 would have been near its stall speed, and unable to pull up.

These data are entirely consistent with the eyewitness observations, which indicate that the aircraft approached steeply, and then tried to pull up when it got too low, but was unable to. It’s also consistent with observations that the engines were powering up just before impact.

Whatever the reason the pilot flew this approach profile, it’s clear that he never had the aircraft established on a stablized approach. FAA Advisory Circular AC 120-71 states that:

An approach is stabilized when all of the following criteria are maintained from 1000 feet HAT [height above touchdown] (or 500 feet HAT in VMC) to landing in the touchdown zone:

  • The airplane is on the correct track. 
  • The airplane is in the proper landing configuration. 
  • After glide path intercept, or after the FAF, or after the derived fly-off point (per Jeppesen) the pilot flying requires no more than normal bracketing corrections2 to maintain the correct track and desired profile (3° descent angle, nominal) to landing within the touchdown zone. Level-off below 1000 feet HAT is not recommended.
  • The airplane speed is within the acceptable range specified in the approved operating manual used by the pilot.
  • The rate of descent is no greater than 1000 fpm. If an unexpected, sustained rate of descent greater than 1000 fpm is encountered during the approach, a missed approach should be performed …
  • Power setting is appropriate for the landing configuration selected, and is within the permissible power range for approach specified in the approved operating manual used by the pilot.

It appears that there is no point in the approach where the approach is stabilized. Indeed, the rate of descent at 600 ft was 1320 ft/min, well above the allowable descent rate. Standard procedure at most airlines would have required the aircraft to go around at that point. However, it’s not clear that standard practice conforms to standard procedure, and  pilots may be reluctant to initiate a go-around at a busy international airport on a clear day.

One other important factor may be that the glideslope signal of the instrument landing system (ILS) was out of service at the time of the accident. It’s standard practice to use the ILS glideslope even when on a visual approach. Indeed, FAR 91.129 (e)(2) requires that, “Each pilot operating a large or turbine-powered airplane approaching to land on a runway served by an instrument approach procedure with vertical guidance, if the airplane is so equipped, must: (i) Operate that airplane at an altitude at or above the glide path between the published final approach fix and the decision altitude (DA), or decision height (DH), as applicable.” Normally pilots would use the ILS glideslope for this purpose. They could have used GPS for vertical guidance (there is an RNAV (GPS) PRM RWY 28L approach), but may not have done so.

It’s far too early to know the cause of the crash of Asiana Airlines flight 214. However, early indications are that it might be due to an unstabilized approach, which is a leading cause of approach and landing accidents. If the cause does turn out to be an unstabilized approach, it will be relatively straightforward for the NTSB to make that determination. The data recorder and cockpit voice recorder will have ample data to determine what decisions the crew made on final approach, what the state of the aircraft was throughout the approach, and what control inputs were applied.

 UPDATE:

At about 4:45 EDT today, the NTSB held a press conference, and it appears most of our conjecture is correct. The target approach speed was 137 kt (not 145). Just before impact, the power was indeed at idle, and the airspeed dropped “significantly below 137 knots and we’re not talking about a few knots.” Seven seconds before impact, a pilot called for increased power. At 4 seconds before impact, the stick shaker actuated, indicating incipient stall. At 1.5 seconds, a pilot called for a go-around, much too late, obviously. So it appears (so far) that our analysis is more or less correct.

 UPDATE 2:

Below is a screenshot of the last part of the final approach path:

UAR 214 Final Approach Path

Here is a link to the KML file for those who may want to visualize more of the flight path.

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169 Responses to What Happened to Asiana Airlines Flight 214?

  1. Brian says:

    Thank you for a nice presentation of the facts. As a commercial pilot, I get frustrated with news media attempts to explain what happened… getting it wrong all the while. Your information is clear and well explained. Thank you.

  2. Birdstrike says:

    Very nice work, particularly with the lack of background in transport jet flying. Just one technical detail to share: “because a 777 is a large aircraft with a large cockpit to wheel height, it would be typical to fly the approach a tad steeper than the standard glideslope.” I think what you meant to say is that it APPEARS to be high on glideslope when you’re looking out of the cockpit windshield of a jumbo jet; the actual glidepath is (or should be, anyway) the same for any aircraft using that runway’s glideslope or papi.

    High-energy approaches have always been tolerated more in the USA than in other countries, partly because of our “let the captain fly his damn plane” mentality of allowing for technique and judgement in unusual situations. In Europe, a high-energy approach is considered a serious matter even if it all turns out ok.

    In this case, it does indeed appear that the crew conducted a high-energy approach thinking that they would get it all worked out a few hundred feet above touchdown, and somewhere along the way, by miscalculation, ended up lower and slower than they wanted to be and didn’t have time to spool-up the engines for a recovery or go around. Usually when a high-energy approach results in an accident, it’s not like this but the opposite: see Southwest at Burbank, Southwest at Chicago Midway, and American Airlines at Kingston, Jamaica. All ended up off the other end of the runway after touching down long and fast, not smacking into the breakwater BEFORE the runway, out of airspeed and power. That’s what makes this one special.

    Thanks to accidents like these, it is now becoming standard practice in the industry to have the entire contents of the Digital Flight Data Recorder uploaded via satellite every 24 hours to analyze flight profiles, configuration, everything. The pilot then gets a nastygram from management if he flies an approach a little high or fast or disregards a cockpit warning. If this trend continues, the day will come that we aren’t even allowed to land the plane manually except in an emergency.

    • Steve says:

      Thanks for the kind words and additional insight. One small nit: You say

      I think what you meant to say is that it APPEARS to be high on glideslope when you’re looking out of the cockpit windshield of a jumbo jet; the actual glidepath is (or should be, anyway) the same for any aircraft using that runway’s glideslope or papi.

      My understanding is that large aircraft fly a PAPI with three white/one red instead of two white/two red, which as you note, puts the wheels of the aircraft at the same height over the threshold. But flying 3W/1R puts the eyes of the pilot 0.25 degree higher, all the way out the approach. That is, flying 3W/1R puts the aircraft cockpit a little higher over the threshold, but significantly higher far out on the approach. The nose of the aircraft is flying a 3.25 deg glideslope, and therefore so is the rest of the plane.

      Again, thanks.

      • Albert says:

        Flying a 3/1 PAPI is incorrect procedure, probably left over from VASI days.
        From FAA docs: “The glideslope of the PAPI
        must provide the proper TCH for the most demanding aircraft height group using the runway.”

        All aircraft should use a 2/2 PAPI approach unless they are operating at an airport which normally doesn’t handle that (large) aircraft type.

    • MikeM says:

      “If this trend continues, the day will come that we aren’t even allowed to land the plane manually except in an emergency.”

      Isn’t this mentality, in part, what contributes to this problem? I know that flying a 777 is a lot more complicated than flying a F-33 Bonanza, but at some point, looking out the window and flying a visual approach is a skill that you have to have if you’re in the pilot’s seat. At some point, doesn’t the over-reliance of flight directors, auto pilots, auto throttle, auto landings, etc. degrade the flying ability of air crews?

      You’ve got at least three pilots, all sitting up front, and they don’t realize that they’re too low and slow in time to go around? How can that happen to guys that are supposed to know how to fly? This isn’t somebody bombing around the local airport in a C-182 with a new ticket and 75 hours TT?

      • Carl Yee says:

        A guy in a C-182 and 75 hrs is probably newly licensed or in training and soloing. But I am sure this pilot knows what the correct sight picture is for a landing that is going to be a greaser. Usually for most pvt pilots, the “best” they are is right after licensing, unless they go on for other ratings.

        I too am amazed that the descent was never stabilized, especially for a plane as big as this one. Someone forgot the basic principles of inertia and they got way behind this airplane.

      • John in Brisbane says:

        Yep – more manual flying is the answer, not less. Aside from the obvious, this Asiana one is looking like a CRM issue to me.

  3. Scott says:

    The 777 flies the exact same glide path as all other airliners.
    Scott
    777 pilot

    • Karl says:

      Thanks for the quick note and id’ing yourself as a 777 pilot! It seems like a little but it said a lot.

    • Pete Pharr says:

      Hi Scott,
      As far as “throttle response” and “time to spool up” with the Pratt (?) engines in the 777, could you elaborate a little on how quickly a half, 3/4 or full power TOGA might have arrested the 800-900 fpt sink rate they carried into the last half mile final (from FlightAware)? Am left wondering at what point, beyond which, the 777 engines would not have been a solution given sink rate, airspeed and altitude. I’d read those engines are “fairly quick” to “spool” at 3-4 seconds, but I don’t know how that equates to “actual thrust” (as in a possible lag after full spool to full power?) Have only flown a little SEL. Thank you.

  4. Mike says:

    Thank you for the physics lecture. Your charts are quite telling. Only now have I fully considered the amount of lifting force (energy) needed to check the high rate of descent (literally falling) of such a large object, which must be achieved prior to a safe landing. It appears as though the aircraft didn’t have sufficient airspeed to generate enough lift to slow the high rate of descent. IMHO, the pilot’s ego kept him from aborting.

    • Marc says:

      Best example of that one is the well reviewed video of the Thunderbird ejection / crash, in which the airplane came out of a loop with too much downward momentum. Even at full thrust and correct attitude, it was not enough to recover.

      Same thing likely happened here (no loop but too much downward momentum). Flightaware had a rather scary reading of 87 kts at 200ft. Way too slow for a large ship like the 777.

      • Steve says:

        I believe the 87 kt reading occurred after impact. The location indicated is actually beyond the final resting point of the fuselage.

  5. Andy Furlong says:

    This is the kind of information I’d like to see on TV. Very informative! Thanks for the clear info.

  6. Mike-san says:

    Very nice and insightful explanation – I wonder if you had this nailed before NTSB could get the “go team” off the ground. :)

    • Karl says:

      Keep in mind that being brief can cause an appearance of arrogance or impoliteness. Neither is the case with my response.

      I’m a pilot with limited experience. My very 1st thought when I heard the nature of the crash was to low & too slow. This would cause a nose high/tail low attitude. Loss of control due to stall and impact. I would guess every single pilot out there thought the same thing right off the bat. Landing 101. We all learned it the first time we were allowed to take controls during training. I know it and I’m sure the NTSB knew it right away. They are still going to investigate and essentially keep their mouths shut.

      • Jim says:

        That was my first thought, especially after seeing the video. I just recently made my first solo going for PPL so I’ve been doing a lot of touch and go’s lately.

  7. Scott says:

    I would also add that un-stabilized approaches are not tolerated at my airline. The Asian carriers in my opinion are much more likely to have Capt’s with god syndrome.

    • Karl says:

      I don’t want to sound stupid but I only know how I would handle a bad approach. When you say “not tolerated” does that mean that the expectation would be that a go around decision would have been made many, many seconds before this pilot seems to have?

    • Nev says:

      Hey guys,

      A very informative post !
      As a B777 Captain for a major Asian carrier we have very strict stabilised approach criteria. If not stabilised completely by 1000 ft AAL we go-around, no questions asked.
      KSFO is always a difficult airport with numerous types of approaches and congested ATC. These arrivals are made so much more difficult when landing after 15 hours in the air, and when your body clock is on your home time zone.

      One thing that I don’t yet understand is why the auto thrust did not power up to maintain speed. Even if disarmed, it has an auto wakeup function that should work in any modes that they would fly an approach in.
      But maybe it was turned off altogether for the visual approach.

      Anyway, I’ll have plenty of time to ponder that point on my way to….KSFO…tonight.

      Regards.

      • Witold says:

        A a B777 pilot, can you fill us in on the workings of the Auto throttle in a high energy approach?

        Would the AT need to be fully disabled so that engines could be idled during approach?

        From your flying experience, could the fully VFR approach procedure have them miss the checklist to enable auto throttle?

        And before we throw these experienced pilots under the bus (as everyone seems to be doing), what could have failed that is not very obvious on the first pass of the FDR?

        Cheers all!

        • Matt Moriarty says:

          777 has an autothrottle “wakeup” feature that will bring the throttles almost to max near the stall.

          However….

          As one pilot very brilliantly puts it, there is something called the “FLCH Trap.” FLCH (flight level change) autopilot mode with FD on will actually disable the wakeup feature. See what he wrote here.

          • Nev says:

            FLCH is a very good mode for changing flight levels, at higher altitudes, but it is not an approach mode.

            However, when being vectored for an approach and the aircraft is too high, an easy way to recover is to set a lower altitude, select FLCH, speed brake etc. this give a high rate of descent, and as long as the pilot has the G/S armed the aircraft will capture it. The G/S acts as a safety net.

            In this case, the aircraft did not level out, and we know the GS was not active. I have seen several times in this situation where the ALT can be inadvertently set to zero. In that case, the auto throttle will not wake up – as it is performing exactly as directed. If zero is set in the ALT window, with FLCH selected, there is no need for any thrust.

            FLCH is what is referred to as a speed on elevator mode. The pilot sets the airspeed, and the elevators raise or lower the nose to maintain that airspeed. However if the flight directors are not followed, for instance if the nose was raised, the speed would decrease.

      • Paul says:

        Very nice analysis indeed, as factual as can with the little info available. In regards to the autothrottle wake up function as mentioned before by Nev : It is unfortunate, but there is a possible situation where it doesnt work. With the autothrottle disarmed, the auto wake up of the autothrottle will indeed function. In SPD or thrust, same thing. However, when doing a visual approach, there is a reasonable chance the FMA told them the autothrottle was in HOLD, and in that state, the auto wake up of the autothrottle system will not come on. It is disabled in that case. Bit of a catch, been told by numerous trainers, tried it on the SIM, and it will not come on when autothrottle system is in HOLD. Only a first officer on the 777, prone to mistakes like anybody else, but fairly sure of this.

        • Nev says:

          Hi Paul, I don’t think the wakeup function will work in FLCH or TOGA mode. That said, I haven’t seen or tried it. Nev.

      • Mogass says:

        Exactly! I too have been wondering the same thing. It is amazing with the amount of automation in a ship such as a “trip seven” there was not any “machine intervention” that would have alerted these vets with tens of thousands of hours logged to make such a rookie mistake.

  8. Allaric says:

    Thanks for the Physics breakdown , as a Physics/Science student I like to tell my friends that most things can be explained through physics and/or chemistry. Your analysis seems correct and corresponds with the recent NTSB news conference report. Your analysis does add the important information of what the plane was doing during its landing decent.

    I also agree with above posters about these “high energy approaches” and that such approaches should be avoided in non-emergency situations. It does seem if high energy approaches were restricted then there would be a reduction in crash landings , such as this AAA214 and other crashes where the planes run off the runway.

  9. Pedro marcal Snr. says:

    When I see accidents like this I always ask the question what automatic override actions could the plane have taken in the last critical time span to avoid the accident. The 777 was aware of the incipient stall speed. It was also probably aware of the momentum caused by the steeper glide path. Finally in crash landing of planes, there is a tendency to pancake. Would a shearing structural design such as those we have on high quality automobiles on unsymmetrical front impacts lessened the damage?

    • Carl Ross says:

      I don’t think Shearing structural design – “crumple zones” would help Pedro, as the aircraft in question hit tail first and a wing lifted significantly, engines ripped off their mounts – you can see that in the video and photos on MSM ( Main stream Media). You also see that the fuselage is significantly “oval- shaped ” at the tail, and more or less still cylindrical and with less damage at the nose from initial impact, it looks like more damage was done to the nose from friction, as it looks like it was trying to curl under the fuselage due to ground friction. This is noted by the bowing of the fuselage window lines in front of the wings all the way to the nose. Beyond that observation Aluminum reacts significantly different from Steel under the same forces, it is much more malleable, and aircraft are less predictable than cars, where impact points can be from any direction in a crash. Most cars are designed to crumple in the front and rear only, with strengthening bars put in the doors.

      • E. Ireland says:

        Considering the high vertical impact velocity, the subsequent skidding & plowing, and the way the aft end came up and around at the end and dropped from perhaps 60 ft, it is hard to fault the airframe’s crash-absorbing capabilities. That is a rugged airframe.

        A little known fact about about the crash behavior of aluminum is that, even under very high crash loads that greatly exceed the metal’s yield point, the metal grains do not have time to permanently deform (yield) before the load is gone. It’s behavior remains almost completely elastic because the overload is so short. So even if a part of a fuselage gets momentarily crumpled into a fraction of its original size, it will immediately spring back almost to its original shape, with little evidence of what it has been through. Controlled crash tests by NASA with high speed cameras have documented this fact.

        This makes it difficult to look at a post-crash airframe and know how much punishment it took, so we need to be cautious in interpreting what we see there.

    • Eric C says:

      It did have a shearing design which likely did lessen the damage. The gear and engines are both designed to shear off before they can rip the wing and wing fuel tanks apart. They seem to have fulfilled that task admirably. Both main gear and engines separated from the plane yet the wings (and, critically, the wing box) stayed intact.

      To your first question, the ability to monitor airplane total energy and report it to the pilot has long been available, though I’m not sure of its use in transport aircraft. The display is typically looks like a glideslope or fast/slow indicator, with a vertical bar and pointer which centers in the middle of it. Even if such a display weren’t presented to the pilot, it would likely not be technically difficult to incorporate an EGPWS warning based off it. I could envision a future warning saying “Too Low, Terrain…. Power Power”.

    • At one of the news conferences yesterday, the NTSB chair said “inside the aircraft there’s significant structural damage.” She was explaining that the plane held together enough to make the crash survivable.

      It doesn’t seem like there is much room on an airframe to put crumple zones. Probably better to keep it strong and work on better passenger restraints.

      • John in Brisbane says:

        Yeah there is some crumple built in but mainly via the wings, gear etc. The seatbelts have some give in them but i’m not sure about the seats. In modern light aircraft the seats will absorb lot of vertical energy – some are rated to 26Gs.

  10. MJ says:

    Thank you for the analysis and posting.

    If the pilot would have had at least a HUD with an FPV, he would have apparently seen it lined up with the “-5″ degree chevrons most of the way down the chute, should the data provided above be correct. This kind of approach is fine for fighter jets with massive excess thrust and available AOA/G margins, but never in a transport.

    The current paradigm in ADI displays as well leaves the pilot with only the yellow and red band of an outsourced colorful speed tape and perhaps pitch limit indicators to tell him/her of impending stall – which in the vast majority of transports provides no tactile warning, hence the stall shaker. All three of these indications (airspeed, PLI, shaker) are one dimensional concepts. Meaning, the only information they provide is deviation from nominal.

    Try driving down the freeway in a car without a spedometer and see how hard it is to precisely maintain 65 mph based solely on what you can glean from the odometer. Or from aural commands from someone sitting in the passenger side yelling only “slow!” and “fast!” repeatedly in your ear. This is the concept of deviation. And it is a relic of the past with us today simply because the civil aviation community has yet to find a way to incorporate what the military has been successfully tuned into for decades – the concept of displaying “energy state” not via airspeed, but rather AOA.

    But regardless of any need for a paradigm shift in display symbology, few things vindicate a crew from chasing a high and fast close-in at the ramp. The acrobatics required to pull that off are graphically displayed above; there is only ONE point of intersection between the flight paths of both 777s. Imagine how hard it would be to show up configured correctly on-speed on-altitude at THAT single point.

    Not a wise move. But then again, ALPA has been arguing with the FAA for years about bad vectoring on the LDA approach leading to un stabilized descents…..

  11. Desert Zephyr says:

    Thank you. I am not a pilot, but found your presentation clear and informative. Once more data is available, I hope you have the time to add to your analysis. This is far better than anything I have seen on the news.

  12. MDS says:

    The first broken chain of events could have saved them. With the ILS out of services then should have used the 28L GPS approach. That would have placed them on the proper glide slope and would have enabled a full auto pilot controlled landing.

    I would bet most comercial operators require coupled approaches even when cleared the visual. With such a large aircraft making large adjustment is unaccetable.
    Too bad.

    • MJ says:

      ….the only other possibility being an erroneously computed VREF due to incorrect pilot entry of aircraft ZFW and CG, but if the data above is correct, it would seem like the classic case of getting behind the jet due to a host of possible factors, leading to an destabilized push over, followed by the command decision to overcorrect a “high and fast” into a “low and slow”, ending up well into the back side of the power curve, where the only option is to descend (or pull into shaker and risk stall).

  13. AspiringSimPilot says:

    Many pilots are criticising pilots/airlines for not wanting to fly visual approaches and depending too much on ILS and here we see an experienced captain training his FO to get some practice and he crashes! Dammed if you do , dammed if you don’t. You can’t win!

    • Cerealspiller says:

      An experienced captain training his FO is standard practice. An experienced captain (and FO) failing to bail when the situation gets out of hand is not.

  14. Murray says:

    One mystery remains: how did the airspeed get so low? Did the thrust stay at idle? How? The 777 autothrottle and engine combination is very responsive in approach mode and should have maintained the selected airspeed regardless of the aircraft vertical profile. The attempted go around would have been possible if the speed had not been so low. In fact, if the ADS data is correct it almost looks like the correct vertical pat