Saturday, February 13, 2021

Dassault Falcon 900EX, N823RC / N718AK: Accident occurred February 13, 2021 at Montgomery-Gibbs Executive Airport (KMYF), Kearny Mesa, San Diego County, California

This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when the final report has been completed. 

The National Transportation Safety Board did not travel to the scene of this accident. 

Additional Participating Entity: 
Federal Aviation Administration / Flight Standards District Office; San Diego, California

Aerospike Iron LLC
Crownair Aviation 


Location: San Diego, CA 
Accident Number: WPR21LA110
Date & Time: February 13, 2021, 11:50 Local
Registration: N823RC
Aircraft: Dassault Falcon 900EX 
Injuries: 5 None
Flight Conducted Under: Part 91: General aviation - Personal

On February 13, 2021 about 1150 Pacific standard time, a Dassault Falcon 900EX, N823RC (formerly N718AK) was substantially damaged when it was involved in an accident in San Diego, California. The two pilots, one additional crew member and two passengers were not injured. The airplane was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 flight.

The flight was being operated as an instrument flight rules cross-country flight from Montgomery Executive Airport (KMYF), San Diego, California, to Kailua/Kona Airport (PHKO), Kailua/Kona, Hawaii.

Reportedly, the flight crew was unable to raise the nose of the airplane at rotation speed (VR). The crew subsequently aborted the takeoff; however, the airplane overran the end of the runway and came to rest approximately 560 ft beyond the departure end of the runway.

Aircraft and Owner/Operator Information

Aircraft Make: Dassault 
Registration: N823RC
Model/Series: Falcon900EX Easy
Aircraft Category: Airplane
Amateur Built: No
Operator: 
Operating Certificate(s) Held: None
Operator Designator Code:

Meteorological Information and Flight Plan

Conditions at Accident Site: VMC 
Condition of Light: Day
Observation Facility, Elevation: KMYF,427 ft msl
Observation Time: 11:00 Local
Distance from Accident Site:
Temperature/Dew Point:
Lowest Cloud Condition: Clear
Wind Speed/Gusts, Direction: / ,
Lowest Ceiling: 
Visibility: 10 miles
Altimeter Setting: 3004 inches Hg 
Type of Flight Plan Filed: IFR
Departure Point: San Diego, CA 
Destination: Kailua/Kona, , HI (PHKO)

Wreckage and Impact Information

Crew Injuries: 3 None
Aircraft Damage: Substantial
Passenger Injuries: 2 None 
Aircraft Fire: None
Ground Injuries: 
Aircraft Explosion: None
Total Injuries: 5 None 
Latitude, Longitude: 32.81511,-117.14104 

    

SAN DIEGO (CNS) – Five people escaped injury Saturday when a corporate jet they were in crashed upon takeoff at the Montgomery-Gibbs Executive Airport in Kearny Mesa, fire officials said.

At 11:47 a.m. Saturday, the jet hit the dirt at the end of the runway and lost its wheels, said Battalion Chief Matt Nilsen of the San Diego Fire-Rescue Department.

Video from the airport shows debris scattered across the ground after the jet hit the dirt at the end of the runway and lost its wheels.

All five people on board got off the jet with no injuries reported, Nilsen said. Fire units arrived at the airport at 3799 John J. Montgomery Drive at 11:54 a.m.

A total of 37 fire personnel were assigned to the crash, including an airport crash rig, two hazmat teams, two fire engines, a medic and two battalion chiefs, according to a fire incident log.



A corporate jet crashed at Montgomery-Gibbs Executive Airport in Kearny Mesa Saturday morning, but no passengers were injured.

The plane was taking off at 11:45 a.m. when the landing gear collapsed, and the jet slid on the ground at the end of the runway, San Diego Fire-Rescue Battalion Chief Matt Nilsen said. None of the five people on board were injured, he said.

The plane landed on its belly and was damaged in the crash.

There was a full tank of fuel aboard the plane, which began leaking after the accident. The fire department’s hazmat team and a crew from county’s Environmental Services Unit were called to clean up the site, Nilsen said.




A corporate jet ran off the runway possibly suffering landing gear failure at Montgomery-Gibbs Executive Airport in Kearny Mesa Saturday, fire officials said.

At around 11:40 a.m., the jet ran off the runway possibly suffering landing gear failure and landed on its belly, the San Diego Fire-Rescue Department said.

No injuries were reported.

A total of 32 fire personnel were assigned to the crash, including an airport crash rig, two hazmat teams, one fire engine, a medic and one battalion chiefs, according to a fire incident log.


Five people escaped injury Saturday when a corporate jet they were in crashed upon takeoff at the Montgomery-Gibbs Executive Airport in Kearny Mesa, fire officials said.

At 11:47 a.m. Saturday, the jet hit the dirt at the end of the runway and lost its wheels, said Battalion Chief Matt Nilsen of the San Diego Fire- Rescue Department.

All five people on board got off the jet with no injuries reported, Nilsen said. Fire units arrived at the airport at 3799 John J. Montgomery Drive at 11:54 a.m.

A total of 37 fire personnel were assigned to the crash, including an airport crash rig, two hazmat teams, two fire engines, a medic and two battalion chiefs, according to a fire incident log.


81 comments:

  1. I was at the airport, watching the various activities from a parking lot often used for casual viewing. This aircraft was parked right there with it's Auxiliary Power Unit (APU - a small jet engine embedded in the aircraft to provided electrical power and compressed air). After at least a half hour, probably more, it finally taxied out. I couldn't see the beginning of the takeoff run as that area was blocked by parked aircraft, but there was a gap between there and the hangars this aircraft had been parked by. I saw it pass by until the hangars blocked the view but as it passed I thought it was odd that at least the nose gear hadn't yet lifted off the ground, although I would have expected the whole aircraft to be in the air by then. I waited around for maybe another 30 seconds or so to see if it would climb above the hangars but I didn't see it. I didn't hear anything and I didn't see any dust or smoke so I figured it must have gotten airborne and was in a position I couldn't see.

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    1. This video shows the beginning and most of the takeoff roll:

      https://youtu.be/W69xSQlH2l8

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    2. The last hangars you see in that video is where the aircraft had been parked and was where I was. One thing I _thought_ I noticed and that the video seems to support is that the nose gear slightly lifted off the runway once or twice. There's a video online that I saw a little while ago - I can't remember where - that shows the aircraft's (non-)takeoff roll to the point of it stopping in a cloud of dust.

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    3. With just over 6300 P.I.C. Hours in the 900EX, after looking at the video from a couple of different internet sites, I was able to see the entire take off run. This accident will clearly be determined pilot error, a violation of V1 planning and execution. For whatever the reason for being on the ground past V1 ( engine failure(s), out of trim, ) max braking with full reverse should have been clearly visible. Thank god for the soft overrun area, a life saver for sure.

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  2. Pilot can be heard on "KMYF Ground #2" LiveAtc archive, Feb-13-2021 1930-2000Z segment.

    Transcription below includes talk of short field takeoff. Dashes shown below represent portions unable to be heard clearly enough to transcribe.

    "Montgomery ground, Falcon eighty two romeo charlie, we're gonna be ready once they uh get to the end there --- a momentary delay for a short field takeoff"

    Followed by a voice saying what sounds like:"You wanna try exactly what's on your -- exam"

    LiveAtc terms of use asks users to NOT directly embed file links. Use link below to navigate to the date and time selector and then reach the file:

    https://www.liveatc.net/archive.php?m=ksan_kmyf_gnd

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    1. Sounds like the controller is the voice that is conveying the info about a momentary delay for a short field takeoff.

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    2. any indication of how short was the requestd "Short field takeoff?"

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    3. @Gbear- Listening carefully again to the recorded voices, it seems like the controller was advising the Falcon that the Falcon would be delayed by some other aircraft making a short field takeoff.

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    4. First thing I thought watching the vid was he must be doing a short field because he was spooling up with the skids on. Just my observation and as usual could be due to any number of reasons. Thankfully all pax are ok but hard to see such a beautiful a/c on its belly like that.

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  3. Here's the tower contact right before takeoff. Starts about 14:45 into the 19:30Z recording.

    https://archive.liveatc.net/kmyf/KMYF1-Twr-Feb-13-2021-1930Z.mp3

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  4. Recent N# change request dated 09/08-2020 from N718AK to N823RC Crown air aviation
    https://registry.faa.gov/AircraftInquiry/Search/NNumberResult?nNumberTxt=718AK

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  5. Takeoff runway length requirement for the 900EX is 5200' at maxGW and 28R at MYF is 4600'. It appears that N823RC/N718AK started the takeoff roll with zero flaps. It also appears that the pilot went to max braking with wing spoilers extended when he realized the plane was not going to leave the ground before the end of the runway. Perhaps a short-field takeoff was the standard takeoff procedure for that aircraft at MYF.

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    1. Flaps were extended and appear to be in the normal takeoff position. The video linked above (here: https://youtu.be/W69xSQlH2l8 ) shows them at 0:44. Seems to be proper, but nose didn't come up when the PF initiated rotation shortly after.

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  6. Takeoff initiated with gear handle in "up" position? Airplane got a little light with speed/lift and the squat switched closed completing the gear up circuit?

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    1. Gear was still down when he ran out of pavement, got sheared off during traversing the dirt beyond the full length of the runway. No gear retraction occurred.

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  7. I've watched another video of a Dassault 900 EX takeoff and noted that there is considerable stabilizer nose up trim used. In the video supplied by Aviationking95, it appears that the stabilizer is trimmed flat, with perhaps even a bit of nose down trim dialed in. Again, referring to Aviationking95's video, at the approximately 0:37 mark, it appears that considerable nose up elevator is being used, yet, the aircraft does not rotate.

    I've been wrong before, but this could be a case of a missed checklist item: the stabilizer trim setting.

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    1. Takeoff videos do make 900s look trimmed for nose up, but it is an illusion. Where paint contrast and lighting angle is good, trim setting can be observed by the position of the horizontal stabilizer leading edge at the base, where there is a raised "arrowhead" bezel.

      Below are two video links where you can clearly see the leading edge of the horizontal stabilizer is aligned to the point of the bezel. The first video is the post crash accident aircraft and the second is a 900EX successfully taking off. (Links start just before where you need to pause)

      Since both aircraft can be observed to have the leading edge aligned to the point of the arrowhead bezel, it appears that the accident aircraft was trimmed the same as the successful takeoff example.

      Accident aircraft (pause at 1:15 and look at bezel):
      https://youtu.be/V4AhVfFIfXQ?t=72

      Example successful takeoff (pause at :41 and look at bezel):
      https://youtu.be/_IvdP3MVZmE?t=38

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    2. Can't be sure of that comparison - if the bezel moves with the stabilizer, the leading edge would always be aligned with the tip. Have to look close at the angle of the surface, just as capngrog suggests. Here is an example from an A310:

      https://youtu.be/6hZQeTrmcjU?t=24

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    3. The "bezel" that you refer to is actually the horizontal-to-vertical stabilizer seal or fairing which moves with the horizontal stabilizer.

      Here is a link to the Dassault Falcon 900EX Easy Systems Summary Manual:

      https://www.smartcockpit.com/docs/F900EX-Flight_Controls.pdf

      If you look at page 13 of the manual, it shows pitch trim indication marks painted on the base of the leading edge of the vertical stabilizer. Unfortunately, the marks are not clear (at least to me) on the otherwise very clear video clip you cited.

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    4. You are correct, capngrog. Wish we could see the marks. While the smartcockpit reference says there are audible and CAS visual warnings if trim is not set for takeoff, there have been plenty of silenced and ignored warnings associated with accidents.

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    5. You can see those reference marks on the CBS 8 post crash video if you pause and zoom in at the 29 second point in 1080p quality. The marks are white on grey background. Definitely not trimmed nose up.

      https://youtu.be/a-1HraosffU?t=29

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    6. ^^^ Typo: Should be "Definitely not trimmed nose down."

      Leading edge of stabilizer is trimmed downward, which is nose up, as required for takeoff per the smartcockpit reference.

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    7. I'm unable to see the reference marks you said were on the CBS video. Can you enlarge the video clip or otherwise enhance it so that we can see the trim marks referenced to the stabilizer leading edge?

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    8. To see the marks, I used a desktop PC to view the youtube video (changing default resolution quality from auto 360p to 1080p using the "gear" symbol at the bottom) and then did a "alt-print screen" of the paused full screen image at the 29 second point to get it on the clipboard and then pasted that into a photo editor, then enlarged the view of the tail.

      If you don't set the youtube quality to 1080p for the screen grab, the default auto 360p resolution in the youtube player makes the screen captured image too blurry when you zoom in to see the marks using a photo editor.

      The white marks show up as one up high and three lower down, just like page 13 of the smartcockpit manual. The tip of the horizontal stabilizer is positioned the same as what is circled in the page 13 image.

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    9. Are you referring to the Fox5 video or the video posted by Aviationking95? It looks like both Aviationking95's post and video have been removed from this forum; however, I found his video on youtube and blew up the image at the 29 second mark as you suggested. Again, I'm unable to see the marks, but that doesn't mean they aren't there. I looked at several on line images of Falcon 900EXs sitting on the ramp and was able to see the trim setting marks. I noticed that when the stabilizer is trimmed as you said (also the angle shown on page 13 of the manual), the top edge of the horizontal stabilizer fairing/seal is approximately horizontal. I was able to see that horizontal angle of the fairing/seal in the post crash video, so without my actually seeing the marks, I accept your analysis that the stabilizer trim setting of the accident aircraft was as shown on page 13 of the manual.

      Now the question is: was that stabilizer trim setting the correct one for this aircraft under the conditions prevailing at the time of the attempted takeoff?

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    10. Here is the CBS 8 video link, screen grab it at 29 seconds on 1080p and take into a photo editor:
      https://youtu.be/a-1HraosffU?t=29

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    11. Ahhh, finally, I see the stabilizer trim marks. Thanks for posting that video link and thanks for your patience.

      My question remains, was it the right stab trim setting for that takeoff?

      I was able to find the video originally posted by Aviationking95 and here is the link:

      https://jetcareers.com/forums/threads/falcon-900-accident-san-diegos-montgomery-field-2-13-2021.307938/#post-3044662

      Notice that at 0:17 of the video, upward deflection of the elevators is not apparent; however, upward deflection is apparent starting at 0:18 in the video. I'm not expert on the Falcon 900EX, but in my recent reading, I've found information to the effect that the 900EX is pretty sensitive to improper takeoff stabilizer trim. Whether or not it was a factor in this crash, remains to be seen.

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    12. Oops, that link was to a site discussing the crash. If you scroll through that site, you can find the link.

      Here's the link (I hope):

      https://twitter.com/i/status/1360704100103430145

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    13. Glad you saw the trim marks. Seems likely that being heavy with a full fuel load for Hawaii on the 4600' runway is the first hole in the cheese. Whether the problem they aborted for was being too slow to rotate, incorrect trim/flaps, etc or an actual technical malfunction will eventually be known.

      Spending a few thousand dollars of increased fuel cost at Lindbergh field and having that 9400' runway there would have supported the abort. Being at MYF for lower cost fuel seems to have contributed to the unfortunate chain of events.

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    14. Possible the control locks were not removed. I'm no Falcon guy, but it could happen.

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    15. I was thinking that too, like the Gulfstream at KBED.

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    16. This may be the reason, but I'm not sure - I only have 2000 hours in the Falcon 900 EASy.

      They were 6000lbs OVERWEIGHT for that airfield... But yeah, it could be the gust locks that don't exist and it might be the trim setting even though they were likely 50 knots slower than rotation speed at 48000+ lbs

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  8. https://m.facebook.com/groups/479832425458958/permalink/3413535605421944/?_rdr video of the full over run accident.

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  9. "FA90X (Dassault Falcon 900EX EASy, Falcon 900DX, Falcon 900LX EASy). The primary flight control systems on the standard aircraft complies. The on-ground gust locking of the control surfaces is accomplished by installing an adjustable nylon strap connecting the pilot's right-hand rudder pedal to the control wheel. This strap is not an integral part of the flight control systems. The presence and, in turn, engagement of the gust lock is unmistakable by the flight crew as it resides in their direct line of interface with the control column and rudder pedals. It is not possible to taxi or to move any of the primary flight controls without first removing the gust lock. Engagement of the gust lock thus requires intentional effort by the flight crew.

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    1. dude - you made all of that up. 100% fiction. Clue: how the hell would a gust lock prevent you from taxiing when the Falcon 900 uses an electric steering tiller?

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  10. I have 4000 hours flying the Falcon 900.
    During the takeoff roll the plane behaved as if the flaps were selected to 7 degrees, rather than 20 degrees. 20 deg is normal. 7 deg is typical for hot, high density altitude conditions. Taking off with flaps at 7 deg requires an increase in V1 (decision speed) with a corresponding increase in takeoff roll. Approximate performance data for this takeoff, assuming it was fully fueled (3,134 lbs) as would typically be needed for the stated flight to Hawaii, and at 15 deg C, flaps 20 deg, would require about 5800'. Flaps 7 deg would require about 800+ feet more runway, or approximately 6600'
    This runway is substantially shorter than that.
    Remember, on paper any Part 25 certified Transport Category airplane, Falcon or 747, is required to be able to continue the takeoff after the V1 call, or stop on the available runway before the V1 call, should a problem occur during the takeoff.
    Sometimes its a simple a problem as a passenger yelling out, "stop, I forgot my cell phone!"
    The crew is trained to manage all this but sometimes it gets complicated and mistakes can be made.
    Whatever the cause it's a very bad, sad day for the crew and their families.
    Its almost a miracle no one was killed.
    My .02 worth.
    Cheers

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    1. You probably intended to write 3,134 gallons of fuel, not lbs of fuel, since 3,134 lbs of jet-a is only 460 gallons and the 900EX has a max fuel load of 21,000 lbs. Can't power three engines to Hawaii on 460 gallons.

      Fuel price made them choose the wrong field. Airnav shows current retail fuel prices for full service jet-a as $4.45 per gallon at MYF and $7.61 a few miles away at SAN (Lindberg Field) where they would have enjoyed 9400' of runway. That fuel price difference cost them the airplane.

      The CBS 8 story reporting that the fire department said the plane was headed to Hawaii, loaded with 3,400 gallons of fuel, two pilots, one crew person, two passengers and the jet experienced a malfunction causing the pilots to abort the take off is at link below:

      https://www.cbs8.com/article/news/local/montgomery-field-jet-crash/509-8d45fc80-6733-49a9-8206-46f7f970ee75

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    2. LOL! yes, gallons.
      Got distracted while typing.
      Good thing I wasn't flying!
      ;>)

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    3. I fly too currently fly the DA900EX EASy. Though hard to see it does appear the aircraft was configured to SF1. Sampling performance numbers with assumed weights the aircraft could have safety become airborne with SF2 (Slat-Flaps 20). If the wing was "clean" the crew would have received a no takeoff warning at power up. Glad they all walked away!

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    4. 100% correct - thank you. How much do you guess they fudged the FMS numbers by? 6000 lbs or so? Likely much more because I agree, it looked like SF1 as they rolled by

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    5. One note: SF2 is not "the normal take off configuration" On the DA EASY, SF 1 is standard. It should also be standard on the Falcon 900 classics as well, but Dassault never retroactively removed the note that prefers SF2.

      The reasoning is that all SF2 gives you is a shorter take off roll - that's it (in any Falcon 900).
      SF 1 requires a little more runway, but gives you a far superior climb gradient and is also quicker and simpler to clean up after take off (one flap movement instead of 2 bearing in mind you have to wait for 10 secs or so before selecting SF1 to clean).
      I took off from RIL a month or so ago and the FMS wouldn't give me SF1 numbers, but SF2 were just fine - because of the climb gradient.
      My philosophy is always use SF1, unless I need SF2 for a shorter runway -
      Of course - SF1 or SF2 is fine - that's my preference

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  11. What is V1 for this plane with this fuel load? It didn't look like it ever got up to speed.

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    1. smart question. this aircraft at that weight was not even remotely close to the speed they needed. They aborted because they knew they'd fudged the performance numbers just to 'try to take off'. They were not even remotely close

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  12. No headwind there to boost lift, was 5 knots from 200 at 11:45 PST.

    KMYF 131930Z AUTO 20007KT 10SM OVC027 14/08 A2997
    KMYF 131935Z AUTO 22008KT 10SM OVC027 14/08 A2997
    KMYF 131940Z AUTO 22009KT 10SM OVC027 14/08 A2997
    KMYF 131945Z AUTO 20005KT 10SM SCT022 OVC027 14/09 A2996
    KMYF 131950Z AUTO 19008KT 10SM BKN025 OVC029 14/09 A2996
    KMYF 131953Z 20006KT 10SM BKN025 OVC030 14/09 A2997
    KMYF 131955Z AUTO 17008KT 10SM BKN022 OVC030 14/09 A2996

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  13. for CYBERCRAIG.....
    What is V1 for this plane with this fuel load...?

    Flaps 7 = 133 (estimate 47,500#)
    Flaps 20 = 124 (")

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    1. Thanks. It looks like they never got there.

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    2. Scroll down and find the twitter link for speeds during takeoff according to ADS-B. One data point was 128 knots. May have been higher than 128 between the 105 knot and 128 not data points.

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    3. So if flaps were set 20 they should have made it?

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    4. Assuming no other issues, yes.
      I real life the pilot not flying makes the V1 cal 5 kts prior to the airspeed indicator actually reaching V1. This allows reaction time for the pilot flying to get the brakes applied AT V!. This IS the correct technique. Example, for a V1 of 124 I would expect to hear the call as the airspeed moved through 119 KIAS.

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  14. Interesting factoids about jets....
    Pretty much the riskiest thing you can do in a jet is a high speed RTO (Rejected Take Off). Typical brief would state, abort for anything up to 80 knots, beyond that only for an engine fire/failure, loss of directional control or if you think the plane just won't fly.
    Basically, your LOOKING for any reason to continue the take off after 80 kts! Even with a problem it should fly and should you need to return at least you have all the available runway plus emergency personnel and equipment can be ready.
    Lots of talk about hear about possible flap position. If the flaps were actually at 7 deg but posted speeds had been calculated for 20 deg the airplane would not know that. In reality, if it was discovered during the roll that the flaps were at the 7 position when 20 was expected, had the crew had immediately moved the flap handle to the flaps 20 position and continued the take off, the plane would have most likely rotated and flown by the end of the runway but this is not how you train. A sim instructor told me once that "in an emergency a crew will either do what they are trained to do, or make something up. Making something up is highly unlikely."
    Performance is fun stuff!

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    1. If the flaps were in the wrong position:
      1: Their posted speed numbers would not be "green" - a mandatory checklist item
      2: As soon as the throttles Arte 60% or so, a NO TAKE OFF warning would scream at them. Instinct is to freeze at that point - stop what you are doing and figure out what the configuration error is (trim, flaps, one engine shut down, whatever)...

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  15. And yet another spin on this event.
    I believe this airframe was built in 2008. Falcon 900 landing gear are subject to a gear overhaul every 12 years. All the landing gear are completely removed from the airframe, and shipped to Florida (I think) for a total overhaul/repair back to new specs. That would have occurred in 2020 for this plane and likely was done in conjunction with the sale/purchase of the plane last year.
    Part of the brief mentioned above states a "loss of directional control".
    As pilots we know that after major maintenance your on high alert for problems for awhile. It's not out of the question that after the gear was subjected to a high degree of molestation that something just failed, that unmistakable feeling that something is wrong.
    Of course, none of this addresses the question and scrutiny of why the plane was full of fuel on a really short runway. Maybe winglets contribute more benefit than I'm aware of. It's my understanding that after market winglets are a mod that doesn't come with modified performance criteria.

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    1. Same poster as above ^^^^^^^^
      This Falcon appears to be a 900 EX eASY. The winglets would be factory and performance numbers for this configuration would be available in the AFM.

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    2. Winglet STC's don't affect take off performance. If they did, they would be included in the AFM supplement that comes with the FAA approved STC. They affect climb performance and altitude mostly through loss of parasitic drag from wing tip vortices

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  16. Speeds during the takeoff run from ADS-B data, overlaid on the field:

    https://twitter.com/benyaffe/status/1360733957252259841/photo/1

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    1. 85 Knots rolling off pavement into the over run shows how difficult it is to visually judge speed from the runoff video.

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  17. Imagine trying to stop 23 tons in 1200 ft from 147 MPH! Not sure I could do that in a car! It doesn't really look violent, but it is!
    Not even sure I saw the Thrust Reverser deploy in the video, and its no wonder. I imagine the pilot in the left seat was doing everything possible to just keep it stopping in a straight line!
    Yike!

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    1. Same poster as ^^^^^^
      I found another video...
      Thrust Reverser DID deploy during the RTO.

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    2. I've watched several videos of this accident from different angles and, the thrust reversers were never deployed. Watch the video following the aircraft down the runway, and pay careful attention to the jet exhaust opening. It was never obstructed, or covered up as you would expect with the deployment of the clamshell reversers.

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    3. Everyone should know that thrust reversing is not allowed to be counted as a reduction in the required BFL, but these guys did deploy that #2 reverser before hitting the dirt. Probably saved the localizer antenna array.

      Watch for a rapid change in the sheen/glint on the dark center exhaust clamshell doors at 23 seconds in the twitter video linked below. Resolution of the video is too poor to let you see the dark painted doors cover the dark exhaust even if you screen snap and enlarge the image, but the sheen/glint change at 23 seconds is clearly the deployment. Easy to see in full screen view on a monitor.

      https://twitter.com/flying_briann/status/1360704100103430145

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    4. The TR did deploy.
      The Falcon 900 series aircraft only have 1 TR, and its located on the center engine. Interestingly, and unlike other business jets with only two engines and TR's on both, the 900 is even approved for using the TR to back the airplane up. This is because the clam shells on the 900 deploy in a horizontal plane rather than a vertical plane. With horizontal reverse thrust debris is not thrown up off the ground so no chance of FODing the engines.

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  18. Here is a short history of the 900EX with some spec's.
    What were these guys thinking? 4600' of runway for an aircraft that needs 5200' at Sea Level ? geez

    https://static1.squarespace.com/static/5567ceb5e4b07a367ae7e71f/t/5ae232bf2b6a2872ae1520ad/1524773569134/Falcon900EX-PerformanceDescription.pdf

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  19. Here's a video of the thrust reverser operational ck on a falcon tri-jet. I know the video says it's a 50EX, but the basic operation is the same.

    https://www.youtube.com/watch?v=P9dXc731pRk

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  20. N823RC video from December shows it (watch at 27 seconds):

    https://youtu.be/6nhWcYd2Ml8

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  21. NTSB report on a 2007 Falcon 900 "no rotation" over run talks about trim setting and on page six, tells about factory pilot advising of requirement to hold the yoke full aft for more than 2 seconds before nose responds at Vr for max weight takeoffs.

    Link below does work, CAROL does not have reports for aviation investigations before 2008.

    https://app.ntsb.gov/pdfgenerator/ReportGeneratorFile.ashx?EventID=20070616X00749&AKey=1&RType=Final&IType=LA

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    1. This is irrelevant. N823RC was massively overweight. The 'trim rabbit hole' only makes any sense if the aircraft is at V2 and ready to rotate.
      This aircraft was either 6000 lbs too heavy or on 1200 feet too small of a runway - period.

      The KSBA incident also involved an unqualified crew who DID NOT perform a weight and balance. The only reason the STAB TRIM conversation came up, is because THEIR insurance company would not cover the hull (due to their non compliance with the policy (non typed pilot, no W&B computed etc). They Sued the manufacturer and the training provider saying that the trim settings in the manual were not specific enough - when they actually make perfect sense.

      Delete
  22. “ Assuming no other issues, yes.
    I real life the pilot not flying makes the V1 cal 5 kts prior to the airspeed indicator actually reaching V1. This allows reaction time for the pilot flying to get the brakes applied AT V!. This IS the correct technique. Example, for a V1 of 124 I would expect to hear the call as the airspeed moved through 119 KIAS.”

    This is NOT the way to do it. You need to look up the definition of V1 in detail.

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  23. Jeff, I don't understand what you're saying? "Call V1 5 kts before V1 ,pilot not flying makes the V1 call 5 kts prior to the airspeed indicator actually reaching V1. This allows reaction time for the pilot flying to get the brakes applied AT V1. This IS the correct technique." But then you say "This is NOT the way to do it. look up the defemination of V1 in detail "
    For your edification:
    Here's the definition of V speeds "in detail".
    https://en.wikipedia.org/wiki/V_speeds

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    1. For Jeff....
      The description of V1 being called a decision speed is antiquated in this day and age. In reality the speed is defined as the maximum speed the plane should be going at the time an action is taken to stop the plane. i.e., brakes, speed brakes (or spoilers, or lift dump as the case may be). The decision to actually take that action must be made prior to reaching V1 to allow for the human factor of reaction time. If for example, the pilot not flying waited, by SOP, to announce V1 at the actual V1 speed it implies that a call to abort could be made right up to the V1 call. I defy any human being to unexpectedly get an abort call 2-4 seconds prior to V1 to actually act on the abort call and get the brakes applied by V1. I guarantee the pilot flying will over shoot V1, thereby invalidating the BFL requirement. At 200+ feet per second even a delay of 2 seconds is more than the length of a football field. It's significant.
      I've flown the Falcon 900 for 16 years, and continue to do so today. I've attended 22 recurrent trainings at FlightSafety International and they teach making the V1 call a few seconds early for the reason stated. We often get spoiled by getting to use runways that are significantly longer than BFL but we train as if they are all minimum length for a reason, unless relief is granted in the AFM (a rolling start is allowed for the Falcon under certain conditions on long runways)
      Now, your comments as to technique and it's association with a definition are unrelated and ambiguous at best. The technique is associated with an SOP, not a definition.
      I use a lot of contract pilots in the Falcon 900 I fly. I see a lot of variables but I guarantee that my brief will include a request that V1 be announced 5 knots prior to actually reaching calculated V1, for the reasons stated.
      Your milage may vary but probably not in a good way.

      Delete
  24. I just retired after 30 years of flying all models of the 737. I'm now a 737 MAX sim instructor. Some years ago the FAA mandated, at least for 121 carriers, that the V1 call be made at least 5kts BELOW the required V1 speed. The idea is to give the pilot time to make a go/no-go decision and be in the reject maneuver BY V1 speed. I believe this was due to knuckleheads who keep rejection takeoffs above V1, sometimes with disastrous results...

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  25. Two questions for all of the jet experienced pilots commenting here:

    1. If your VIP aircraft owner had you piloting his Falcon 900EX, would you agree to conduct that fueled for nonstop to Hawaii takeoff on a 4600' runway?

    2. Would your decision be swayed if you were aware that the VIP owner kept the jet at the 4600' runway-length field, had the jet under maintenance with an excellent jet center there and enjoyed a significant fuel cost savings?

    Asking because the rejected takeoff would have been a non-event at nearby SAN's 9400' of runway if the jet was re-positioned there for full-load fueling.

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    1. 1. NO!
      2. And, hell NO!
      50 years of clean record, high pay from high net worth owner flying their personal jets, most Falcon 900's.
      Primary rule I follow is, "no one is going to ever tell my son's that their dad is dead cause he was stupid.
      Follow the rules, that's what your paid to do. VIP might not alway like it, and it can occasionally be inconvenient but if that is a problem get a job somewhere else.
      I learned early on to not spoil my owner. Its all worked out great!

      Can you imagine the Insurance company telling this owner, "sorry, we aren't paying for any of this mess cause the plane should never have moved from the ramp!" Unless someone can prove the numbers supported a compliant take off and someone can prove the brakes failed his will take years to sort out. It will get ugly. I can imagine how many law suits will come out of this.

      Delete
  26. I believe we are paid to say no. I put it that way because many say we get the "big bucks" for many other reasons. I believe many may be able to do the job of flying, big jets or little jets, and many are fearful of saying no when faced with an unsafe situation but thats exactly what your experience and confidence should lead you to when the situation is unsafe, or potentially unsafe. Say NO.

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  27. Here's the deal on this incident - I am awesome, so I'm gonna share what happened based on plenty of hours flying that model of aircraft.

    This aircraft is being reported from many places as having full fuel - training center where these clowns trained, the manufacturer and also from the reporting on the day.
    Additional clue: The were cleared to FL360 - that is a MTOW altitude for the Falcon 900EZ.
    The only hesitation I have in believing they weren't full fuel (21000 lbs approx), is that NO competant pilot WOULD EVER consider doing it (the numbers aren't even in the same realm of possibility as doable numbers (think 6000 lbs too much fuel). The other reason is that the FMS will tell you if you can take off (runway, weight fuel on board, flaps position and loading is all factored), If the EASy system says you need 1 inch more runway than you have, it will not compute (so these guys grossly mis-computed the system in order to let the aircraft think it could take off (lied to the FMS (think 12K fuel load entered manually instead of letting the aircraft sense the 21000 lbs on board).
    These guys seem to have been trying to take off in SF1 (flaps 7 degrees) setting from what it looks like on the video. This setting (instead of SF2), would require another 600 feet or so of runway.

    For those saying the gear handle was up - No it wasn't. The aircraft wouldn't take off like that. The gear is designed to mechanically sheer off during a runway excursion. This aircraft behaved as it was designed.
    For those going down the stab trim rabbit hole based on the KSBA incident - totally irrelevant. This aircraft never got anywhere near rotation speed - it was very simply massively overweight. No trim setting will get a Falcon 900EX EASy weighing 48000 lbs plus in 4600 feet.

    These clowns - yes clowns (I mean the low time right seater crashed the sim multiple times during training a month or so prior), obviously had very little time in the Falcon 900EX, or they wouldn't have dreamed they could take off from that runway to Kona. They fudged the FMS numbers to get a take off computation from the EASy system that was so far detached from reality, it couldn't have been an error. They knew their weight as the FL 360 clearance (that they took from their flight planning service), but lied to the FMS, to get airborne.

    These guys should not be flying aircraft and they are all lucky that the numbers were so badly off, that they saw 1/2 way down the runway that they had more chance of taking off in the line guy's golf cart than that aircraft.

    Eternal shame on them for being so foolish

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    1. 100% Agree ^^^^^^^^
      From a guy that also has a bunch of Falcon 900 time.

      Delete
  28. Preliminary report came out, not much detail:

    "Reportedly, the flight crew was unable to raising the nose of the airplane at rotation speed (VR). The crew subsequently aborted the takeoff; however, the airplane overran the end of the runway and came to rest approximately 560 ft beyond the departure end of the runway."

    https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/102629/pdf

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    1. "crew was unable to raising"... Spell check wins again.

      Delete
  29. There have been rumors that the PIC (Left Seat) had no type rating for the aircraft and his pilot certificates were previously revoked.

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    1. How were they filing flight plans, obtaining insurance etc...? This seems to explain the absolute ignorance of what a Falcon 900EX EASy can do and what it can't... It makes the whole incident make sense if this is the case...

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  30. Jeez, the initial report is awful... Just knowing the fuel load would tell us all we need to know. From there, you can compute speeds and take off performance. Pilots are not described - not even labelled as current or qualified.. (?). Come on NTSB... This is basic information.

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