I worked out altitude data. Based on this data, here is what I found:
8,000 feet 3 minutes from touchdown
3,500 feet 5 nm from runway
1,500 feet 4 nm from runway
1,300 feet 1 minute from touchdown
nm=nautical miles
fpm = feet per minute descending
35,000 feet to 10,000 feet in 13 minutes (1,900 fpm descent)
10,000 feet to touchdown in 4 minutes (2,500 fpm descent)
10,000 feet to 2,000 feet in 120 seconds (4,000 fpm descent)
8,000 feet to 2,000 feet in 90 seconds (4,000 fpm descent)
8,000 feet to 1,300 feet in 120 seconds (3,300 fpm descent)
Possible explanation for why pilots forgot the gear:
Can someone tell me if this is possible?
- Plane is at 35,000 feet.
- ATC tells plane to descend to 10,000 feet
- Plane descends to 10,000 feet
- ATC tells plane to descend from 10,000 to waypoint
- Pilots take too long to start descending and then rapidly dump altitude to descend in order to meet waypoint since they have less time
- Pilots continue rapid descent dumping altitude quickly. At 8,000 feet, they were 3 minutes from runway, at 1,300 feet they were 1 minute from the runway. So they descended 6,000 feet in 90 seconds.
- Plane approaches waypoint at too high an altitude.
- At 5 nm waypoint from runway, plane should be 1,700 feet, but it was actually at 3,500 feet (too high).
- ATC offers pilots a circling vector so they can circle and dump excess altitude and approach waypoint a 2nd time at a lower altitude.
- Pilots decline ATC’s offer for circling vector to burn off and dump excess altitude, they tell ATC they can make ILS 25L from their current altitude 3,500 (which is too high).
- Plane was 3,500 feet at 5nm, 1,500 feet at 4nm. So they dumped 2,000 feet in 1 nm.
- During this rapid descent, pilots tried to lower gear earlier than usual to reduce speed and dump altitude.
- Pilot moves gear lever in cockpit in down position for gear down, but plane was going too fast to extend the gear so pilots got an overspeed warning, indicating gear cannot extend while plane is going faster than 260kts, but lever does not move back to up position, lever stays in down position even though overspeed warning means the landing gear is actually in up position.
- Pilots complete landing checklist, lever in down position indicates that gear is down as normal. Cockpit gear lever in down position at approach speed near runway also means that no EGPWS alarm would not be going off, when in reality the overspeed warning earlier means the landing gear is actually still in up position. Since gear overspeed warning only sounds when plane is faster than 260kts, the plane would be slower than 260kts near the runway and the gear overspeed warning would have turned off. Since cockpit gear lever is in correct down position as normal, and lever in down position means EGPWS thinks gear is down, EGPWS alarm is not going off. In reality, the gear overspeed warning earlier in the flight was ignored by accident because the pilots should have moved cockpit gear lever back in up position immediately after getting overspeed warning, slow down below 260kts, and then try second time to move gear lever into down position again at a lower speed. The gear lever does not automatically move back up if you get an overspeed warning, so if you forget to immediately put the lever back up when gear fails to go down, later you will think that gear lever is correct as showing gear down when it is actually wrong and gear is up. After several minutes, pilots may have forgotten that they never tried to lower the gear again a second time after the gear overspeed warning and thought it was already down based on the fact that gear lever in cockpit was in correct position (which they forgot to move back up since overspeed warning meant gear did not go down) and no EGPWS alarm was going off. In reality, since the gear lever did not automatically move back up when overspeed warning failed to extend gear, pilots thought their landing gear was down when it was actually in up position.
- Plane is approaching runway very fast at high speed, everything else looks normal, gear lever is down, no alarms are going off.
- Plane hits the ground on just engines, this is the first time pilots realize that gear is up, big surprise to pilots. The first point that the plane touches down is halfway along the runway, so only half of the runway is left when they first hit the ground.
- Engines scrape ground causing black skid marks
- Pilot instinct is to pull up and abort a bad landing which is what they are trained to do. Since the plane was already coming in very fast and touched down halfway along the runway, pilots were already thinking about going around even before landing, and with half the runway left, they knew they would overshoot the end of the runway if they tried to stop so they aborted instead.
- Plane goes around for 2nd landing attempt
- Plane circles in air for 5 minutes to get back to runway
- During these 5 minutes, hydraulic fluid and oil is rapidly leaking out from pipes that were scraped on bottom of engine. Fuel is NOT leaking out.
- Total loss of hydraulic failure after all hydraulic fluid leaks out from ruptured hydraulic pipes on bottom of both scraped engines, flaps stop working and landing gear issues get worse. White smoke in PSPK picture is hydraulic fluid leaking out of bottom of the scraped engine.
- All oil rapidly leaks out from oil sumps on bottom of both scraped engines, without oil both engines overheat and shut down, plane now becomes glider with no thrust. Fan blades in engine are intact which means engines were not running when plane crashed.
- Ram Air Turbine automatically deploys when both engines shut down to power critical electronics in cockpit.
- Since both engines stop working, plane rapidly loses altitude and starts gliding.
- PSPK picture with RAT deployed is taken
- Landing gear is manually deployed by gravity drop increasing drag and makes gliding more difficult
- Plane loses even more altitude as it makes left turn over Model Colony to line up with 25L
- Plane lines up with 25L but it lost too much altitude by deploying gear early and then lost more altitude by making turn to 25L. Plane is now critically low and cannot make it to runway.
- Plane was only leaking hydraulic fluid and oil, not fuel so there is plenty of fuel left when plane crashes causing massive fireball on CCTV video.
It turns out the theory that the plane had gear down and then bounced and aborted a hard landing, retracted gear early, and scraped engine is wrong. Gear retraction takes 8 seconds so if plane had retracted gear after bounce but before TOGA thrust kicks in, it would have bounced back down in 1-2 seconds while gear retraction takes 8 seconds. There would not have been enough time for landing gear to fully retract in only a 1-2 second bounce. Landing gear doors would have been ripped off at the same time the engines scraped the ground like in Smartlynx incident in Estonia. We know from PSPK pictures that landing gear doors are clean, there is no sign of any damage or ripped landing gear doors. So this means only way it could have no damage to landing gear doors is if landing gear was never deployed in the first place, and only engines scraped ground. The very long skid marks on runway could be either because TOGA took a long time to spool up since friction would make it hard to get airborne again, or alternatively it could be because TOGA in Airbus is not a button like in Boeing, you have to push throttle levers all the way forward to activate TOGA, if you only moves throttle partially, it will not activate TOGA. So this could have delayed response by a few seconds.
Huge question is why did ATC not say a word if they saw a plane coming for approach with no landing gear?
