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AirWillie6475
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Jetblue LAX Landing

Thu Sep 22, 2005 1:07 pm

Great landing by the Blue pilots and how bout that a320, I was really impressed that the gear didn't collapse with all that stress. It shows that they really are built with quality, Airbus will proably sell even more a320s after this one. Anyways my question is why didn't the pilots use thrust reversers in this case, the aircraft ended up only about 1000 feet from the end of the 9000 foot runway.
 
60Victor
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 1:21 pm

Could it be that they did not apply the thrust reversers as this would have
put more down pressure on the front landing gear?
 
cdfmxtech
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 1:23 pm

As you probably noticed, the crew tried to hold off of the nose gear as long as possible so things would be smooth. Once they couldn't keep it off the ground anymore and the NG make contact they then probably applied heavy brakes.

Reverse thrust and spoilers (which you will note they didn't deploy) would have made it harder to keep the nose off the ground.
 
lizzard71
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 2:16 pm

Anybody with a working knowledge of the Airbus nose gear/steering have any insight into how this occurred?
All the posts on the civil aviation forum (on this subject) are just blahblahblah.
Thanks.
lizzard71
 
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HAWK21M
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 2:17 pm


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The Pilots wanted to delay loading the Faulty NLG for as long as possible.By using T/Rs that would purpose have been defeated.
Anyone aware of the A320 NLG.What caused the 90 deg shift.Why didn't the centering cams come into play.
regds
MEL
 
airxliban
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 2:23 pm

Incidentally, am I right in saying that the 737 doesn't have the fuel dump manifolds either?
 
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HAWK21M
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 2:52 pm

Quoting AirxLiban (Reply 5):
Incidentally, am I right in saying that the 737 doesn't have the fuel dump manifolds either

Thats Right.No Fuel Dumping provision on the B737.
regds
MEL
 
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Starlionblue
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 3:02 pm

Quoting AirxLiban (Reply 5):
Incidentally, am I right in saying that the 737 doesn't have the fuel dump manifolds either?

You are correct in that the 737 has no fuel dumping system either. These tend to be installed only on heavies. There is really no point on a plane of this size since it can easily land at maximum take off weight with no structural problems.

However, if there is time and no other mechanical problems are present, burning off fuel (like yesterday) is an option in order to decrease landing speed.
 
vikkyvik
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 4:08 pm

Hmmm...I have a few questions for you pilots/mx/whatever people out there based on this landing. First, can you use wheel brakes while the nosegear is not in contact with the ground? I would think not, due to moments being generated, but I may be wrong. I ask because in this situation, where they held the nose up for what looked like 3,000 feet or so at least, that uses up a lot of runway with just aerodynamic braking.

Secondly, would you use maximum braking in this situation? I would assume so, but I'm just curious, as the airplane used up quite a bit of runway (though that might have been due to keeping the nose up).

I am pretty impressed that the nosegear didn't collapse, though I guess I really shouldn't be. It looks a lot more flimsy than it is, I'm sure.

Thirdly, is this sort of situation either discussed or practiced in the sim during flight training? Seems like such a remote possibility.

Fourthly (is that a word?), if I remember correctly, there is a speed on takeoff (and, I assume, landing) where the steering switches from nosegear to rudder. What speed is this usually at?

On a sidenote, I just heard an ad for KCAL news, where they said, "It took off from New York, but made an emergency landing at LAX." I laughed. But this brings up my final question/comment: The A320 took off from BUR for JFK. That's 2500 odd miles, and Burbank's longest runway is 6,886 feet. When I flew cross-country recently from BOS to LAX (a few hundred more miles) on a 738, we took off on runway 22L (10,005 feet) from Boston though most flights were using 22R (7,860 feet). I'm very impressed that an A320 can take off from a less-than-7,000 foot runway and fly cross-country.


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Thanks guys; as always, I appreciate your input.

~Vik
 
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Starlionblue
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 4:22 pm

Second question: I don't think max braking was used. There is enough runway for the plane to brake gently. This was one of the reasons LAX was chosen.

Third question: As you say the nose gear is quite strong. Think about the fact that even in normal ops the stresses on it can be quite high.

Fourth question: there is no actual speed when it "switches" but under around eighty knots (depending on model) nose wheel steering is used since the rudder doesn't have enough authority. Above around 80 knots, the nose wheel is centered.

Quoting Vikkyvik (Reply 8):
I'm very impressed that an A320 can take off from a less-than-7,000 foot runway and fly cross-country.

There could be payload restrictions, but I really don't know.
 
vikkyvik
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 5:07 pm

Quoting AirWillie6475 (Reply 10):
Vikkyvik, thanks for hijacking the thread.

Sorry man, but I didn't want to start another thread about this landing. There tends to be one thread about other incidents soon after they happen, so I figured I'd ask my questions in this thread. Now, I'm one of those people who reads the whole thread before replying, so in my mind, someone would still answer your original question, as well as others that crop up in the replies. If my original post is a problem, suggest deletion.

~Vik
 
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zeke
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 5:30 pm

Some very reasonable reason suggested above, however a lot of rubbish also.

The A320 QRH 2.13 LDG WITH ABNORMAL L/G provides the answers to some of the above questions....

Firstly for a nose gear problem, you are to move some passenger to the rear of the aircraft to move the CG rearward, 10 from the from will be 4% change in CG, 10 from the middle 2.5%.

AUTOBRAKE ..... DO NOT ARM
REVERSE ......... DO NOT USE
NOSE ............. MAINTAIN UP
BRAKES .......... APPLY
ENG MASTERS .. OFF (shutdown the engines before nose impact)

Shutting down the engines shuts down the hydraulic systems and flight controls. Still have brake accumulator pressure.
 
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Starlionblue
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 6:46 pm

Quoting Zeke (Reply 12):
Firstly for a nose gear problem, you are to move some passenger to the rear of the aircraft to move the CG rearward, 10 from the from will be 4% change in CG, 10 from the middle 2.5%.

So what do you do if the plane is full?
 
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zeke
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 7:16 pm

Quoting Starlionblue (Reply 13):
So what do you do if the plane is full?

Continue with the checklist
 
calpilot
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 8:52 pm

Quoting Vikkyvik (Reply 8):
First, can you use wheel brakes while the nosegear is not in contact with the ground? I would think not, due to moments being

Yes, you can apply breaks before nose wheel is on the ground.

Quoting Vikkyvik (Reply 8):
Secondly, would you use maximum braking in this situation

He used auto-brakes. I would have choosen "Med"

Quoting Vikkyvik (Reply 8):
Thirdly, is this sort of situation either discussed or practiced in the sim during flight training? Seems like such a remote possibility.

I don't remember discussing a canted nosewheel. However, I have practiced in small aircraft, and the B727 many time holding the nose of the aircraft off.

Quoting Vikkyvik (Reply 8):
Fourthly (is that a word?), if I remember correctly, there is a speed on takeoff (and, I assume, landing) where the steering switches from nosegear to rudder.

The Boeing does not switch, we simply have rudder pedal steering that has enough authority to keep control without the need for tiller movement.
 
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Starlionblue
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 9:38 pm

Quoting CALPilot (Reply 14):
The Boeing does not switch, we simply have rudder pedal steering that has enough authority to keep control without the need for tiller movement.

So does Airbus. The rudder pedals move the nosewheel a small amount to either side as well as the rudder. So it's transparent for the pilots. But some planes, like the MD-80, require a 80 knot callout so that the Captain can let go of the tiller.
 
PPVRA
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 9:39 pm

As far as the reverse thrusters go, couldn't they have veered the a/c sideways off it's near-perfect center line landing? The pilot has pretty much zero control of the aircraft, the last thing he wants is some sort of asymmetric (wind/aerodynamic, whatever else) force acting upon the a/c, no? Yes, I know there are engines on both sides, but still...

Also, the R/T vibrations would put more pressure on the gear.

Cheers
 
F14D4ever
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 10:06 pm

Quoting PPVRA (Reply 16):
As far as the reverse thrusters go, couldn't they have veered the a/c sideways off it's near-perfect center line landing? The pilot has pretty much zero control of the aircraft, the last thing he wants is some sort of asymmetric (wind/aerodynamic, whatever else) force acting upon the a/c, no? Yes, I know there are engines on both sides, but still...

They didn't really need a 'near-perfect' centerline landing; just keeping it on the runway would have sufficed, and there's plenty of main gear braking authority to facilitate that.

Quoting PPVRA (Reply 16):
Also, the R/T vibrations would put more pressure on the gear.

Vibrations were not the issue.

Quoting 60Victor (Reply 1):
Could it be that they did not apply the thrust reversers as this would have
put more down pressure on the front landing gear?

As '60Victor' has guessed, reverse thrust creates a significant nose-down moment on the aircraft, exactly what they don't want in this scenario.
 
glidepath73
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 10:21 pm

One friend of mine (He works for Airbus) says, the reason for the blocking steering system on the nose wheel was maybe caused be a overpressure in the nitrogen bubble inside the nose wheel damper system.
If you fill to much nitrogen in there, a possible blocking of the steering system is very likely.

Can anybody confirm this?

Seems the incident was possible caused again by a maintenance mistake.

Regards,
Patrick

[Edited 2005-09-22 15:24:20]

[Edited 2005-09-22 15:32:24]
 
PPVRA
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 10:56 pm

Quoting F14D4ever (Reply 17):
Quoting PPVRA (Reply 16):
Also, the R/T vibrations would put more pressure on the gear.

Vibrations were not the issue.

The gear breaking was the issue. Increasing vibrations further would have contributed to that, no?

Cheers
 
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zeke
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RE: Jetblue LAX Landing

Thu Sep 22, 2005 11:06 pm

Quoting CALPilot (Reply 14):
He used auto-brakes. I would have choosen "Med"

Why do so when the checklist clearly states use no autobrake ?
 
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litz
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RE: Jetblue LAX Landing

Fri Sep 23, 2005 1:48 am

Quoting Starlionblue (Reply 9):
Third question: As you say the nose gear is quite strong. Think about the fact that even in normal ops the stresses on it can be quite high.

Not only that, but when you look at the HDTV video shot of the landing (from a local LA station's news helicopter) you can even see the shocks on the nose gear flexing when the plane halts.

So not only did the nose strut survive, but its shock absorbers were still working perfectly. That's one strong piece of engineering ...

- litz
 
calpilot
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RE: Jetblue LAX Landing

Fri Sep 23, 2005 3:22 am

Quoting Zeke (Reply 20):
Why do so when the checklist clearly states use no autobrake ?

Zeke, which checklist title are you looking at for the Bus, for this situation?

I have nothing in the Boeing book titled "Sideways nosegear landing."
 
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CCA
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RE: Jetblue LAX Landing

Fri Sep 23, 2005 3:57 am

A similar incident.

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CCA
 
highflier92660
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RE: Jetblue LAX Landing

Fri Sep 23, 2005 4:31 am

Unfortunately this incident is a case of deja vu. As I watched the macro media coverage unfold along with many of you, I had a sense that I'd heard of an identical Airbus A320 landing with the nose gear positioned perpendicular at 90 degrees. I was correct.

On February 16, 1999 at CMH, an America West A320 landed with the tires rotated at 90 degrees and, as in the LAX incident, landed without a collapse of the nose gear. A post- landing inspection showed an extrusion of the O ring seals on the steering control module. Further, it had occurred at least three times prior to the America West aircraft and a service bulletin had been issued. Clearly a more severe follow-up is warranted if the Jet Blue A/C is found to have the identical problem.

The report is on the NTSB website.
 
Sabenaboy
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RE: Jetblue LAX Landing

Fri Sep 23, 2005 6:09 am

Here's a link to the NTSB report about the America West incident in feb; 1999:
http://www.ntsb.gov/ntsb/brief2.asp?...205X00227&ntsbno=NYC99IA062&akey=1

In the America west incident, the flight crew received indications of dual landing gear control and interface unit (LGCIU) faults.

It's possible the Jetblue crew had the same indication. (Dual LGCIU fault)

In that case they simply did not use reverse, because with a dual LGCIU failure, both thrust reversers are inop.
 
B744F
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RE: Jetblue LAX Landing

Fri Sep 23, 2005 7:36 am

Quoting Vikkyvik (Reply 8):
I'm very impressed that an A320 can take off from a less-than-7,000 foot runway and fly cross-country.

It barely can, it has had to make fuel stops in Buffalo in the past. Not sure if they are still doing it
 
LeanOfPeak
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RE: Jetblue LAX Landing

Fri Sep 23, 2005 7:50 am

Max braking would have been ill-advised. Braking transfers even more weight to the nose gear than the thrust reversers do.
 
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Starlionblue
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RE: Jetblue LAX Landing

Fri Sep 23, 2005 8:19 am

Quoting LeanOfPeak (Reply 27):
Max braking would have been ill-advised. Braking transfers even more weight to the nose gear than the thrust reversers do.

Exactly. Once the pilot had put it down in the touchdown zone, he knew there was no need to stand on the brakes. Gentle deceleration is easier to control and puts less stress on the strut. It's not like you'll suddenly encounter a small hill in the middle of the runway which will catch the nose gear strut and flip the plane over (just kidding, I meant break the strut).
 
EMBQA
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RE: Jetblue LAX Landing

Fri Sep 23, 2005 8:28 am

....

Quoting AirWillie6475 (Thread starter):
and how bout that a320, I was really impressed that the gear didn't collapse with all that stress. It shows that they really are built with quality, Airbus will proably sell even more a320s after this one.

It's just a real shame the design of the A320 most likely caused this event. The A320, unlike many aircraft does not have a mechanical centering cam in the nose gear. A mechanical centering cam would have prevented this from occuring. The centering on the A320 is computer controlled and something I found strange from a co-worker with many years on the A320... the default on the A320 nose gear computer is designed to turn 90* if it fails...just like what happened last night. Why would you design something to fail like that...?

[Edited 2005-09-23 01:37:00]
 
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HAWK21M
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RE: Jetblue LAX Landing

Fri Sep 23, 2005 2:06 pm

Quoting Highflier92660 (Reply 24):
as in the LAX incident, landed without a collapse of the nose gear.

Arn't there Fuse bolts on the LG.

Quoting EMBQA (Reply 29):
A mechanical centering cam would have prevented this from occuring.

Exactly what I was thinking.

Quoting EMBQA (Reply 29):
the default on the A320 nose gear computer is designed to turn 90* if it fails...just like what happened last night. Why would you design something to fail like that

Why 90 deg.

regds
MEL
 
L-188
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RE: Jetblue LAX Landing

Fri Sep 23, 2005 2:38 pm

Quoting LeanOfPeak (Reply 27):
Max braking would have been ill-advised. Braking transfers even more weight to the nose gear than the thrust reversers do.

Exactly the nose is going to drop when the tail does not have enough airspeed flowing over it to provide sufficent down force to keep the nose up. Doesn't matter if it happens quickly or gently.

Quoting EMBQA (Reply 29):
the default on the A320 nose gear computer is designed to turn 90* if it fails...just like what happened last night. Why would you design something to fail like that...?

It's French? Need I say more...............
 
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Starlionblue
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RE: Jetblue LAX Landing

Fri Sep 23, 2005 6:19 pm

Quoting L-188 (Reply 31):
Quoting EMBQA (Reply 29):
the default on the A320 nose gear computer is designed to turn 90* if it fails...just like what happened last night. Why would you design something to fail like that...?

It's French? Need I say more...............

I don't know about the gear design but I know that it doesn't seem to have caused any fatal accidents. Good enough for me.

Airbus apparently issued a service bulletin for the problem in 1998. Operators have had 7 years to fix the issue. If they choose not to, that's fine by me (it's not an AD) as long as they realize they may end up in the situation the JetBlue 320 was in.
 
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zeke
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RE: Jetblue LAX Landing

Fri Sep 23, 2005 7:33 pm

Quoting CALPilot (Reply 22):
Zeke, which checklist title are you looking at for the Bus, for this situation?

LDG WITH ABNORMAL L/G, its in the QRH and FCOM VOL 3, covers problems with nose gear, partial or both main gear up nose gear down.

For nose gear problems, it assumes the worst will happen, i.e. the strut will collapse and the engine nacelles make contact with the ground.

The checklist calls for use of no autobrake, and no reverse, and for the engines masters off after the main wheel touch prior to the nose wheel touch to cut fuel to the engines in case the strut does collapse.

This means no reverse, and limited hydraulics. Hydraulics is available for 30 seconds after engine shutdown, The priorities for the hydraulics is for to be able to fly the nose onto the ground, and directional control via brakes and rudder. The bakes have a separate accumulator which is sufficient to stop the aircraft in any emergency situation, e.g. loss of two hydraulic systems with a flapless high speed landing.
 
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HAWK21M
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RE: Jetblue LAX Landing

Fri Sep 23, 2005 10:22 pm

What made the crew doubt.Was it inability to Retract NLG.And was a confirmation done by Tower.
Whats the Story.
regds
MEL
 
Stoicescu
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RE: Jetblue LAX Landing

Fri Sep 23, 2005 11:14 pm

Quoting EMBQA (Reply 29):

It is easier to keep the plane on the rwy if the gear rotated 90 than if it rotated 45 for example.
If it rotated 90 there is a lot of drag but it won't affect the rollout but if is 45 the plane will tend to move that side.

I think is a great feature!
 
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777wt
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RE: Jetblue LAX Landing

Sat Sep 24, 2005 12:44 am

Quoting Vikkyvik (Reply 8):
Fourthly (is that a word?), if I remember correctly, there is a speed on takeoff (and, I assume, landing) where the steering switches from nosegear to rudder. What speed is this usually at?

Some aircrafts don't switch over from tiller to rudder automatically. The rudder is effective between 60-80 kts.
So once you past 60 knots, you would want to focus on the rudder for yaw direction rather than the tiller.
 
planespotting
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RE: Jetblue LAX Landing

Sat Sep 24, 2005 1:33 am

I have worked out the thrust reversal geometry on paper, unfortunately I am unable to post it on here.

when the airplane first landed, there is obviously some amount of thrust being produced by the engines, along with the kinetic energy of the airplane. So there is momentum and a slight amount of thurst. The main reason the airplane is moving forward is from the momentum. The wings are still producing a slight amount of lift, but the large amount of drag (flaps, spoilers, landing gear, etc...) and the weight of the airplane are basically cancelling the lift, so the airplane is basically in equilibriam on that side of the equation (the lift side). The airplane is also decelerating somewhat. Without thurst reversal, the majority of the weight of the airplane is on the mains, with the nose gear supporting that of the nose and not too far of an area behind the nose gear itself.

So if the pilots would have applied reverse thrust, the thrust line of the engines shifts 180 degrees. The deceleration would intensify drastically. Because of the spoiled lift and loss of rearward thrust (less moment on the rear wheels) and the deceleration (greater moment on the nose gear), the nose gear takes a much larger portion of the weight of the fuselage past the main gears.

This is all conceptual as I don't want to take the time to come up with the real numbers and equations, but the theory behind it is pretty easy to understand.
 
2H4
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RE: Jetblue LAX Landing

Sat Sep 24, 2005 2:01 am




Quoting Starlionblue (Reply 32):
I don't know about the gear design but I know that it doesn't seem to have caused any fatal accidents. Good enough for me.



Not for me. When it comes to aviation safety, I think the key is to be PROactive, rather than reactive. Minor failures and incidents can expose the possibility of potentially serious problems in the future. It all comes down to observation, anticipation, and prevention.




2H4


 
LeanOfPeak
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RE: Jetblue LAX Landing

Sat Sep 24, 2005 2:03 am

Thrust reversal and braking load the nosewheel because they produce a decelerative force below the aircraft's CG. An aft force below the CG generates a nose-down moment, and the only place a resolving moment can be generated is with a net upward force on the nose gear trunnion.

For this reason (Since the CG of an aircraft, car, etc. will always be above the tires' contact patch), braking will ALWAYS produce a weight shift towards the forward contact patches.

For an A320, reverse thrust will also always produce a weight shift towards the nose gear. For some other types, reverse thrust is nearly weight-shift-neutral, or might even unload the nose gear somewhat.


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...just for a couple of examples.

A thrustline above the CG leads to an undesirable in-flight handling characteristic that could be called negative throttle coupling; An increase in throttle results in trim changing towards nose-down and a decrease in throttle results in trim changing towards nose-up. This not only is counterintuitive, but when you decrease throttle, that will result in the plane slowing down AND a nose-up tendency that will slow the plane down even more (And vice versa for a throttle increase). However, it would be desirable in this case because 1) The engines are implied by a high thrustline to be up and away in the event of a nosegear collapse and 2) A bit of reverse thrust would, at least in theory, allow greater deceleration (And the use of a shorter runway) without loading the nosegear excessively.
 
NKP S2
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RE: Jetblue LAX Landing

Sat Sep 24, 2005 2:27 am

Quoting 2H4 (Reply 38):
Not for me. When it comes to aviation safety, I think the key is to be PROactive, rather than reactive. Minor failures and incidents can expose the possibility of potentially serious problems in the future. It all comes down to observation, anticipation, and prevention.

I agree. "Good enough" adequacy seems to have seeped in and corrupted commercial aviation as it attempts to slowly establish a paradigm. Many accidents result from an unfortunate chain of relatively minor, in and of themselves, problems. In any event, just because a situation does not result in a smoking hole in the ground doesn't make it inherently adequate. Issues can crop up resulting in increased sevice difficulties and downtime.

[Edited 2005-09-23 19:30:33]
 
MidnightMike
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RE: Jetblue LAX Landing

Sat Sep 24, 2005 2:35 am

Here is a video of the landing:

http://www.ifilm.com/ifilmdetail/2676093
 
2H4
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RE: Jetblue LAX Landing

Sat Sep 24, 2005 2:38 am




Here are a couple more nosegear alignment-related photos from the DB:






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Photo © Erwin






2H4


 
Brick
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RE: Jetblue LAX Landing

Sat Sep 24, 2005 4:17 am

Quoting Vikkyvik (Reply 8):
I'm very impressed that an A320 can take off from a less-than-7,000 foot runway and fly cross-country.

The BUR-JFK flight is weight restricted:

http://www.flyertalk.com/forum/showthread.php?t=425814
 
sovietjet
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RE: Jetblue LAX Landing

Sat Sep 24, 2005 5:03 am

I have one question, how did they figure out it was off center in the first place? Is there an indicator that the nosewheel is not centered?
 
calpilot
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RE: Jetblue LAX Landing

Sat Sep 24, 2005 5:15 am

Quoting Zeke (Reply 33):
LDG WITH ABNORMAL L/G, its in the QRH and FCOM VOL 3, covers problems with nose gear, partial or both

Zeke, I think the Bus has a great checklist with that. Going through my book, I have to force myself into either a checklist "Partial or Gear UP" or "Gear will not move". Neither gives guidance with respect to A/B's or or Reverse.

Of course common sense would rule out the REV., but for me in this case I think I like the idea of MED Brakes starting the deceleration, and being ready for unequal breaking taking me off center line.

Heck, between you and me I'm going to consider auto-land too. And then go with hand flying.
 
mrocktor
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RE: Jetblue LAX Landing

Sat Sep 24, 2005 5:54 am

Quoting Sovietjet (Reply 44):
I have one question, how did they figure out it was off center in the first place? Is there an indicator that the nosewheel is not centered?

I'm not familiar with the A320 specifically, but I'm pretty sure they noticed something was wrong because the nose gear would not retract. Whether they have some indication of steering position or the failure was visually verified during a fly by, I don't know.

mrocktor
 
Slcpilot
Posts: 614
Joined: Thu Aug 07, 2003 3:32 am

RE: Jetblue LAX Landing

Sat Sep 24, 2005 6:22 am

LeanOfPeak,

It may be down in the details, but this is "Tech/Ops", so what the heck...

I think if braking is occuring with the main wheels, reverse thrust, even below the CG of the aircraft, will result in a lighter load on the nosewheel.

Consider this extreme example. You're sitting on the ramp with the parking brake set. You apply full reverse thrust, will the weight on the nosewheel increase or decrease? I maintain it will decrease. Draw the free body vector diagram and consider the moments about the point of contact between the main wheels and the ground.

I think there are obviously more things to consider, and I'd go by the QRH given the choice, but I've always enjoyed statics problems...

SLCPilot


PS. Have you ever heard about how you can back up a B-17 with no beta?
 
Sabenaboy
Posts: 183
Joined: Tue Feb 20, 2001 5:31 pm

RE: Jetblue LAX Landing

Sat Sep 24, 2005 6:22 am

They had a landing gear shock absorber fault + nosewheel steer fault.
In that case the checklist calls for a max speed of 280kts/.67 and not to retract the L/G. (The L/G retract is inop anyway)

The airbus FCOM states that the nosewheel may be turned 90 degrees of center with these indications.

The checklist only calls for: during landing, delay nosewheel touchdown for as long as possible.

Source: Fcom 3.02.32 page 1

[Edited for spelling]

[Edited 2005-09-23 23:29:09]
 
2H4
Posts: 7960
Joined: Tue Oct 19, 2004 11:11 pm

RE: Jetblue LAX Landing

Sat Sep 24, 2005 6:57 am




Quoting Sabenaboy (Reply 48):
The checklist only calls for: during landing, delay nosewheel touchdown for as long as possible.



Does the Airbus FBW software limit the amount of up elevator deflection during rollout? In other words, would a 737, for example, permit more up elevator deflection during rollout, to effectively hold the nosewheel off of the ground for a longer period of time?




2H4


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