"Nobody can find a single person able to offer a simple technical explanation. Hard landing suggests they were either fast or long and in a hurry to get it down to start slowing, which is a pilot error. You're supposed to go around."
Writes rhhardin (in the comments to the previous post).
Here's a typical article on the Pence plane incident, short on technical substance and padded with fluff — like Pence throwing a football at some earlier point in the day, the choice of food on the flight (salmon or pork, the pork with "loaded potato"), the Secret Service joke before the landing ("93 percent chance we crash"), the view from the window ("Grass and mud starts coming up"), the thoughts in the head of one passenger ("Are we going to stop in the water? Are we going to stop in the grass? Are we going to hit something? … What’s the end game here?”), the smell ("like rubber, like burnt rubber"), quotes from people who didn't know what happened ("We were trying to figure out what the f--- had happened"), and the difficulty passengers had getting reconnected with their luggage.
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Any landing you can walk away from is a good landing.
Also? Only two kinds of landings: Navy or Air Force. This sounds like Navy and a missed cable.
There are several possibilities. First, it could be pilot error. Second, there could have been insistence by a Pence representative to the pilot ordering him to land regardless of the potential danger. This apparently happened to the Poles. Third, it could be a sudden gust of wind or rain. But, fourth, it is well known that LaGuardia is a dangerous airport. Half the run way is on dry land, and half which is over the water. The section over the water can behave very differently than the section over the land. I acknowledge that these possibilities are not mutually exclusive.
Thorby said...
First, it could be pilot error. Second, there could have been insistence by a Pence representative to the pilot ordering him to land regardless of the potential danger.
If the pilot landed at the insistence of a Pence representative, against his own judgement, that is still pilot error. ( If he landed at the insistence of the Secret Service, due to some security issue, that is a different matter. )
First thought...The Clinton Crime Family had something to do with it....
Thorby: good point about LGA. Bumpy air on landing is no fun anywhere but when you take (1) weather and potential downdrafts or other significant and sudden changes in lift due to gusts/microbursts plus (2) approach over water and then abruptly over land (with possible discontinuities due to differential warming) plus (3) heavy traffic plus possibly (4) demanding clientele -- it's a miracle anybody gets in and out of that airport. Kudos to the pilots and ATCs who keep us safe.
Owen, above, is correct about the difference between AF and Navy landings. Most AF bases have 11, 000 ft runways and smooth "grease job" roll-outs are the standard. Navy ac have to dissipate forward momentum quickly which a heavy impact landing does by dissipating energy and thus forward momentum. The same may be said for either AF or commercial ac on slick or icy runways where a firm runway "plant" upon touchdown is the approved technique for dissipating forward rolling energy.
Navy ac have to dissipate forward momentum quickly which a heavy impact landing does by dissipating energy and thus forward momentum.
It doesn't dissipate anything but lets you get the wheels on the ground where you can brake with them and use reverse thrust without falling out of the sky, sooner.
Wheel landings (on a taildragger) stop quicker than stall landings for that reason, though they don't have to be done hard. Hard just might indicate that there's no time for finesse.
The pilot probably should have gone around, but I've never seen a large commercial jet do a go around, and I can see the 4 runways at LAX from my back yard. Of course they're between 9700 - 12000 ft long.
It's ridiculous, but good fun to speculate. Too much ground speed at touchdown or failure of the thrust reversers or failure to deploy thrust reversers. NTSB will finger it out in 15-months to be pilot error of some sort. It's always pilot error except in those rare cases when something breaks. Pilot error is the price of pilot in command.
Bago: Was in a 737 doing a go-around on final to SFO last July. It was because of traffic. Had the grandkid with and cooly explained it to them so it was fun, not scary.
" I've never seen a large commercial jet do a go around"
We did a go around in Tucson one time on a very windy summer day.
I still wonder about the thrust reversers.
A hard landing does indeed dissipate energy, as a crash landing shows in the extreme. The force on the runway and the plane is dissipated momentum, but I don't know how much that adds up to shortening of the runout, and if it results in a bounce then it is gonna lengthen it. Maximum stopping effect requires maximizing the down force, and duration in contact. Reverse thrust is separate from this component, except that you can't do that during a bounce either. The shortest landing at a given speed is a hard landing without any bounce. Of course the shortest landing is a nose dive - no reverse thrusting needed, and no passenger complaints to listen to.
If you fly enough, you eventually do a go around. Or a landing abort. I remember at least twice, once into PHX. Most of the passengers didn't really realize what was going on, but I had flown enough into these airports that I recognized what was going on. Those were the years when I was doing over a 100 flights a year. Don't regret leaving that at all, though you do get used to it. I still fall asleep on the takeoff roll, almost automatically.
The force on the runway and the plane is dissipated momentum
Only vertical momentum. The horizontal is unchanged.
It doesn't dissipate anything but lets you get the wheels on the ground where you can brake with them and use reverse thrust without falling out of the sky, sooner.
Most fighter aircraft do not have thrust reversers. In fact on carrier landings the touchdown is accomplished with takeoff thrust set in order to prepare the aircraft to fly should the cables be missed.
On this mishap, I would be very suprised if it is not determined that the approach was unstable, meaning that either the aircraft was either above the glideslope or that it was carrying too much airpeed or possible both. Configuration, flap settings or even landing gear is also a consideration in whether the approach was stable or not. In any case most operators have sop's that require a go around if the approach is outside of clearly defined parameters. There are generally slightly different parameters depending on weather conditions, but last night it was certainly IMC instrument meteorological conditions in the NY area, which would require the approach to be stable, certainly no later than 1000 ft above the ground.
I fly the Boeing 777 for a living.
Depending on the weather, you determine your stability, i.e., condition of the airplane, approach parameters and overall conditions at either 1000 or 500 feet above touchdown. If you're "unstable," the Pilot Monitoring," (the guy not flying) calls "Unstable" and, depending on circumstances, "Go around." (abort the landing and climb/begin the missed approach/clean up, e.g., reset flaps for the go-around and raise the gear once you're climbing).
You can call for a go-around even after touching down, until you apply reverse thrust, at which point it's too dangerous to do so.
What actually happened is anyone's guess...and at this point just a guess. As a trained accident investigator, trust me when I say that accurate witness testimony is rare at best. Better to examine the cockpit voice recorder, the data recorder, ATC tapes, etc., before jumping to conclusions.
Think I've shared this story before here, but it always cracks me up to think of it. Back during Valujet days, I flew from Dallas to Atlanta, and experienced the worst landing of my life on a commercial flight. I swear the pilot almost - and I mean it was close - ground-looped the thing.
Debarking, the pilot was man enough to stand at the cockpit doorway and apologize to the passengers for the rough landing. Older gentlemen in front of me got pissy after receiving his apology and said, "Well, I'm a college professor, and if I were grading that landing it would absolutely be a 'D'". Pilot, without skipping a beat, replied "Luckily for us all professor landings are pass/fail."
I am just now reading the news reports. Interesting the comments about how the pax had become accustomed to "bad landings." It lookslike maybe the campaign is leasing this plane from the new Eastern airlines. If so I would be curious to know what the level of experience the Captain and First Officer have. Both in total time and time in type(737). As someone who has operated in and out of LGA over many years in multiple types of transport category aircraft I can say that those approaches and landings at night with heavy rain and gusty crosswinds are definitely the ones where my pulse gets elevated. DCA is another with its 7000 ft runways and proximity to water on both ends.
It looks as if the EMAS (crushable concrete arrestor) did its job and prevented the a/c from ending up on the grand central parkway.
A10pilot, thanks for your comments. Fascinating stuff for us non-pilots.
bagoh20 said...The pilot probably should have gone around...
Probably should have landed at a better airport.
Its been a month since the hoboken train crash. Most likely 'pilot' error. But no official reports yet
Flying out of or into Burbank-Bob Hope on 737s or DC9s (MD80s) had its moments. Southwest Airlines landed one of its 737s long one night on the shorter of the two runways. Ran right through the airport fence and into the gas station across the road. Luckily the gas station didn't blow up.
Landed one time on a hot summer day in a PSA DC-9 that had taken a full load of fuel on in the morning at San Diego. Whoo had, almost made the fence "exit" across Hollywood Avenue at the airport boundary.
Flew out of the airport several times a month for years; in January and February, the climbout towards San Francisco or Oakland across the San Gabriel mountains was always an E Ticket ride with lots of violent turbulence. The wind blew down through the passes and it could be brutal in the winter. Didn't smooth out until you were past the Tehachapis.
Had a near mid air in a UAL 727 climbing out of SeaTac.
The point of all this is that occasionally "stuff" happens in commercial or charter aviation. And only a moron at the NYT would "diagnose" the problem without any more knowledge then maybe playing a video game one time back at NumbNuts U before getting into the NYT "news" room.
With the exception of one, there are many on this thread eager to be ac landing experts. A bit more difficult perhaps than landing an arm chair.
"With the exception of one"
Well 2 really. Except I actually operate at LGA on a regular basis. You don't see many twin aisle birds there. There just isn't enough room.
I guess Politico figures that there's an important politician involved so they have to say something or another. But outside of the implication that the pilot routinely made rough landings there's nothing there that they know for a fact except Pence tossing footballs while he waited to take off (shades of JFK!) and the food served on board. Oh, and the plane went off the runway.
But did you catch that bit about the reporters being miffed at having to wait for their luggage? If I was on an aircraft that slid off the runway I'd be happy to be uninjured and content to wait a bit for my suitcases. Not the entitled few who call themselves "journalists."
There used to be, on youtube, a very neat unstabilized landing by some east European 737, with a continuous turn from base to runway, no final approach proper. He overshot the turn a half runway width and had to change the bank angle at the end but otherwise it was a very nice thing to watch.
He wasn't hot or high.
That used to be an early morning entertainment before the tower opened for business with light planes.
One additional thing to get perfect, the turn rate, besides height and speed.
That's in good visibility though.
Discussion of LGA weather at the time shows that the winds at the airport just after the accident were from 100 degrees or out of the southeast at 10 knots gusting to 15 knots.
The aircraft landed on runway 22(heading 220 degrees magnetic). That 120 degree difference means that they were experiencing a quartering tailwind component between 5 and 7 knots. That same hourly observation also included moderate rain.
Not a great scenario (737 max tailwind is 10 kts, sometimes 15) but assuming they used their approved method to determine required landing distance and determined they had enough runway to land given the landing weight, weather, and runway condition it was not prohibited. In fact I bet scores of aircraft landed just prior to them without incident.
The wind conditions clearly favored landing in the opposite direction on runway 4, however changing runways at LGA involves coordination and reconfiguring arrival and departure traffic at all 3 airports (EWR and JFK) due to their proximity, so its not done without some planning. What needs to happen is for that one guy/gal to say NO. I'm not going to accept that, and maybe get the process started. Of course, NY controllers love it when pilots tell them how to do their job. Really, they are some of the best in the world IMHO.
The magic word for s "UNABLE."
320Bus, FWIW, we're sitting #1 for 36L at MEM watching company launch into a bunch of yellow and magenta on the WX scope. The cockpit conversation went something like, "What do you think?" ... "Oh, HELL no." ... "Yep." Next fall to tower, "Umm, Memphis Tower, were just gonna sit tight until departure looks a little better" ... "Roger"....002 nanoseconds later, everybody behind us radioed, "Me too."
Pilots would rather die than look bad, especially us old Attack guys...but I got my limits.
That was next CALL to tower.
A10...yup, you can almost hear the collective sighs of relief in those instances.
Our FOQA people are always happier when they see a healthy number of go arounds in their data.
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