A380 MLG Tire Scuffing/Skidding
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Perhaps off the rim was an incorrect assessment.
Naturaly I meant that these tires have deformed a considerable ammount. And judging by the skid marks have been dragged a good bit.
Naturaly I meant that these tires have deformed a considerable ammount. And judging by the skid marks have been dragged a good bit.
Join Date: Jul 2005
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It was a test - results normal
The test is a normal part of the ground testing of the aircraft, and the results exceeded expectations - the gear is tested to failure. All is fine. The test consists of towing the aircraft, at maximum weight, forward, backward, in normal turns, in tight turns, and laterally. The goal is to assess the landing gear's structural integrity in all directions in abusive cases. The test does not replicate normal aircraft operations.
Below is a story that was posted on Flight International's on-line daily news service - Air Transport Intelligence:
A380 tyres withstand extreme handling tests: Airbus
London (15Jul05, 12:01 GMT, 174 words)
Airbus is claiming that the undercarriage and tyres on its A380 aircraft have performed as expected after being subjected to extreme ground-handling tests last month.
Images show that the tests resulted in deformation and damage to the aircraft’s Michelin tyres but that they performed “at and above” expected levels during the abusive ground-handling tests on 25 June.
The A380 main undercarriage comprises two four-wheel under-wing bogies and, behind them, two six-wheel fuselage-mounted bogies. The rear axle of the six-wheel bogie is normally steerable during push-back and taxiing.
But unless electrical power is supplied to the aircraft during towing - by the aircraft or from generators on the tow-tractor - the axle remains locked.
Airbus states that the undercarriage tests were designed to take the undercarriage and tyres “way beyond the limit of normal operations” and adds: “[The tests] were the equivalent of the structural static airframe tests to destruction.
“Although these tests were designed to test up to maximum deformation and beyond, the gear did exactly what it is supposed to do.”
Below is a story that was posted on Flight International's on-line daily news service - Air Transport Intelligence:
A380 tyres withstand extreme handling tests: Airbus
London (15Jul05, 12:01 GMT, 174 words)
Airbus is claiming that the undercarriage and tyres on its A380 aircraft have performed as expected after being subjected to extreme ground-handling tests last month.
Images show that the tests resulted in deformation and damage to the aircraft’s Michelin tyres but that they performed “at and above” expected levels during the abusive ground-handling tests on 25 June.
The A380 main undercarriage comprises two four-wheel under-wing bogies and, behind them, two six-wheel fuselage-mounted bogies. The rear axle of the six-wheel bogie is normally steerable during push-back and taxiing.
But unless electrical power is supplied to the aircraft during towing - by the aircraft or from generators on the tow-tractor - the axle remains locked.
Airbus states that the undercarriage tests were designed to take the undercarriage and tyres “way beyond the limit of normal operations” and adds: “[The tests] were the equivalent of the structural static airframe tests to destruction.
“Although these tests were designed to test up to maximum deformation and beyond, the gear did exactly what it is supposed to do.”
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thefacts - I have to say that your crude effort to deflect speculation and the repeated excercise of bias by the introduction of inconvenient facts is unlikely to work. But it's a nice try nonetheless!
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Gentlemen,
sorry to disappoint you and your expectations or theories. "Thefacts' s" infos are correct. Forget all the fuss about it. Ask your tech. or fleet pilots in your company involved in introducing the A 380. They (we) are always keen to explain, but not in a public forum.
What a bowl of experts here.
Regards
sorry to disappoint you and your expectations or theories. "Thefacts' s" infos are correct. Forget all the fuss about it. Ask your tech. or fleet pilots in your company involved in introducing the A 380. They (we) are always keen to explain, but not in a public forum.
What a bowl of experts here.
Regards
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According the following link to a newspaper THEFACTS is right.
http://money.excite.com/jsp/nw/nwdt_...&date=20050715
http://money.excite.com/jsp/nw/nwdt_...&date=20050715
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http://images.airliners.net/open.fil...=862819&size=L
For thsoe that think it isnt the 380
For thsoe that think it isnt the 380
Join Date: May 2002
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I may be wrong, but what I see are 3 legs with 4 whells each
the only two candidate in this configuration are IL86 and A340-600
Yes I understand that the pics is even coming from the Airbuss gallery but the clearance from the body and he whells does'nt look to me the one of the 600.
I may be probably very Wrong, anyway great pics amazing stress test. I can't really figure out how this can happen. Where is the center of rotation ?
I apologize to every body to bothering about the IL86 story.
But I couldn\'t see even the body reflection the 3rd axel of the Body Landing gear. bye
the only two candidate in this configuration are IL86 and A340-600
Yes I understand that the pics is even coming from the Airbuss gallery but the clearance from the body and he whells does'nt look to me the one of the 600.
I may be probably very Wrong, anyway great pics amazing stress test. I can't really figure out how this can happen. Where is the center of rotation ?
I apologize to every body to bothering about the IL86 story.
But I couldn\'t see even the body reflection the 3rd axel of the Body Landing gear. bye
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"... pictures from intentionally destructive testing ... "
Maybe a dumb question, but was this F-WWOW?
If so, are they sure the gear was not over-stressed or are they replacing the gear?
And what about the structure around the attachment points?
Maybe a dumb question, but was this F-WWOW?
If so, are they sure the gear was not over-stressed or are they replacing the gear?
And what about the structure around the attachment points?
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The pictures were taken on 25 June during ground load testing as
part of the standard aircraft verification test. The aircraft was at
maximum ramp weight with rear C of G position and no body gear steering
(steerable aft axle) available. The aircraft was then towed and pushed into
turns at maximum nose gear steering angles. In these 'worst case' scenarios
the strains on the gear are measured to ensure structural integrity. The
tests confirmed that, given the gear deformation built up, no tug driver
would ever bring the aircraft to the extreme steering angles achieved
during this particular load testing.
part of the standard aircraft verification test. The aircraft was at
maximum ramp weight with rear C of G position and no body gear steering
(steerable aft axle) available. The aircraft was then towed and pushed into
turns at maximum nose gear steering angles. In these 'worst case' scenarios
the strains on the gear are measured to ensure structural integrity. The
tests confirmed that, given the gear deformation built up, no tug driver
would ever bring the aircraft to the extreme steering angles achieved
during this particular load testing.
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Like all new aircraft, weight under stress tests are necessary.
By the look of it, that's exactly what these images illustrate.
Turn the nosewheel, full opposite power and watch what happens.
Will the tyres come off the rims?
Will the tyres burst?
Will the carriage bend as it is supposed to?
All quite normal.
Panic over.
Err, like what Iceland said ...
By the look of it, that's exactly what these images illustrate.
Turn the nosewheel, full opposite power and watch what happens.
Will the tyres come off the rims?
Will the tyres burst?
Will the carriage bend as it is supposed to?
All quite normal.
Panic over.
Err, like what Iceland said ...
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All covered in the Flight international article wasn't it? Tests designed to push the gear beyond limits to assess how much abuse the gear can take.
I wonder how close the origin of the scare stories was to Seattle?
I wonder how close the origin of the scare stories was to Seattle?
Thread Starter
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Air Transport
Airbus A380 Gear Put Through Drills
Aviation Week & Space Technology
07/25/2005, page 42
Michael A. Dornheim
Los Angeles
Robert Wall
Paris
A380 tires damage airport surface during 'abusive' turn test
Gear Concerns
Airbus is being forced to respond to Internet-circulated pictures of A380 tow tests, which show the landing gear carving grooves in the asphalt during turns sharper than normal limits. Reaction pushed the company to issue a letter to "airline focal points" on July 19.
Officials at Airbus and Goodrich, which engineered and builds the main landing gear, insist the results validate their design and they do not plan any changes. "Although spectacular for the non-specialist, actual deformations are not as high as on some other aircraft," Airbus wrote to the airlines. "Preliminary results confirm the design values of loads and deformations."
But while they are happy with the gear, others--such as airport operators--see the torn tarmac and wonder what will happen to their property. Some want more information, such as how strong the damaged asphalt was.
The June 25 tow tests at Toulouse were intended to stress the landing gear during "abusive cases" outside normal operation, Airbus says. During the trials, the gross weight was 546 metric tons (1,204,000 lb.); maximum takeoff weight for the aircraft is 560 tons. The tests consisted of "towing and pushback maneuvers at high weight, with various nose-landing-gear steering angles ranging from typical operational values up to extreme cases, close to bottoming of steering actuators, beyond the allowed towing/pushback limits," Airbus says.
Maximum steering angle for the A380 during towing will be restricted to a standard 60 deg., Airbus says. The tests were performed at 60 deg. and higher, reaching a maximum of 72 deg.
"Given the gear deformation buildup, no truck driver would ever bring the aircraft to the extreme steering angles achieved during this particular loads testing," Airbus says.
The A380 has four main landing gear, two on the body with six-wheel trucks and two on the wing with four-wheel trucks. The wing gear are forward of the body gear. On an aircraft with a simpler single-axle main landing gear, the axes of the nosewheel and the main wheels intersect at the center of the turning radius. But multiple main gear axles form parallel lines that can't intersect at the turning center, and some of the tires have to scrub laterally in a turn. The sharper the turn, the more they scrub. The Boeing 747 alleviates this problem by steering the body gear at low speeds so the axes point toward a common turning center, which reduces scrubbing.
THE ENTIRE A380 body gear doesn't steer, but the aft axle does steer on the six-wheel trucks. If the body steering mechanism is inoperative, the A380 can be dispatched with the wheels aligned and locked. The wing gear do not steer at all. In these photos, it is the wing gear that are scrubbing. The tests were the first in a series to check A380 ground handling. In August-September, Airbus plans to assess minimum turn radius at heavy weight and taxiing the aircraft with engines running. U-turns are also on the to-do list.
Airbus officials have begun trying to explain the situation, saying the tests marked a positive step in verifying that the A380 can taxi using FAA Design Group V or ICAO Code E runway/taxiway systems--a standard measure for those surfaces.
FOR THE JUNE 25 TEST, body wheel steering was deactivated. The aircraft was near its maximum weight, with an aft center of gravity, to represent a worst-case condition. The test procedure consisted in towing/pushing the aircraft out and into a turn. When the turn radius was stabilized, the aircraft was stopped, and pictures of the landing gear were taken.
Airbus officials note that given the roughly 90F temperature on the day of the test, and the fact that the aircraft was turned beyond set limits, "it is not abnormal to have some local deterioration of the asphalt." But one airport official quipped: "Ninety degrees? Is that all?"
Three tires were replaced after the test. This wasn't mandatory, Airbus says, but helped with the flight test schedule.
Airbus expects the A380 to be able to perform U-turns in a similar or smaller space than the A340-600 due to its shorter wheelbase. Moreover, the company points out that with 20 main landing gear wheels, the per-wheel weight on the A380 is lower than Boeing's 777-300ER.
_
_
Airbus A380 Gear Put Through Drills
Aviation Week & Space Technology
07/25/2005, page 42
Michael A. Dornheim
Los Angeles
Robert Wall
Paris
A380 tires damage airport surface during 'abusive' turn test
Gear Concerns
Airbus is being forced to respond to Internet-circulated pictures of A380 tow tests, which show the landing gear carving grooves in the asphalt during turns sharper than normal limits. Reaction pushed the company to issue a letter to "airline focal points" on July 19.
Officials at Airbus and Goodrich, which engineered and builds the main landing gear, insist the results validate their design and they do not plan any changes. "Although spectacular for the non-specialist, actual deformations are not as high as on some other aircraft," Airbus wrote to the airlines. "Preliminary results confirm the design values of loads and deformations."
But while they are happy with the gear, others--such as airport operators--see the torn tarmac and wonder what will happen to their property. Some want more information, such as how strong the damaged asphalt was.
The June 25 tow tests at Toulouse were intended to stress the landing gear during "abusive cases" outside normal operation, Airbus says. During the trials, the gross weight was 546 metric tons (1,204,000 lb.); maximum takeoff weight for the aircraft is 560 tons. The tests consisted of "towing and pushback maneuvers at high weight, with various nose-landing-gear steering angles ranging from typical operational values up to extreme cases, close to bottoming of steering actuators, beyond the allowed towing/pushback limits," Airbus says.
Maximum steering angle for the A380 during towing will be restricted to a standard 60 deg., Airbus says. The tests were performed at 60 deg. and higher, reaching a maximum of 72 deg.
"Given the gear deformation buildup, no truck driver would ever bring the aircraft to the extreme steering angles achieved during this particular loads testing," Airbus says.
The A380 has four main landing gear, two on the body with six-wheel trucks and two on the wing with four-wheel trucks. The wing gear are forward of the body gear. On an aircraft with a simpler single-axle main landing gear, the axes of the nosewheel and the main wheels intersect at the center of the turning radius. But multiple main gear axles form parallel lines that can't intersect at the turning center, and some of the tires have to scrub laterally in a turn. The sharper the turn, the more they scrub. The Boeing 747 alleviates this problem by steering the body gear at low speeds so the axes point toward a common turning center, which reduces scrubbing.
THE ENTIRE A380 body gear doesn't steer, but the aft axle does steer on the six-wheel trucks. If the body steering mechanism is inoperative, the A380 can be dispatched with the wheels aligned and locked. The wing gear do not steer at all. In these photos, it is the wing gear that are scrubbing. The tests were the first in a series to check A380 ground handling. In August-September, Airbus plans to assess minimum turn radius at heavy weight and taxiing the aircraft with engines running. U-turns are also on the to-do list.
Airbus officials have begun trying to explain the situation, saying the tests marked a positive step in verifying that the A380 can taxi using FAA Design Group V or ICAO Code E runway/taxiway systems--a standard measure for those surfaces.
FOR THE JUNE 25 TEST, body wheel steering was deactivated. The aircraft was near its maximum weight, with an aft center of gravity, to represent a worst-case condition. The test procedure consisted in towing/pushing the aircraft out and into a turn. When the turn radius was stabilized, the aircraft was stopped, and pictures of the landing gear were taken.
Airbus officials note that given the roughly 90F temperature on the day of the test, and the fact that the aircraft was turned beyond set limits, "it is not abnormal to have some local deterioration of the asphalt." But one airport official quipped: "Ninety degrees? Is that all?"
Three tires were replaced after the test. This wasn't mandatory, Airbus says, but helped with the flight test schedule.
Airbus expects the A380 to be able to perform U-turns in a similar or smaller space than the A340-600 due to its shorter wheelbase. Moreover, the company points out that with 20 main landing gear wheels, the per-wheel weight on the A380 is lower than Boeing's 777-300ER.
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_
