Author Topic: pushback ends with destruction of nose gear - crash  (Read 4058 times)

Moach

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pushback ends with destruction of nose gear - crash
« on: May 19, 2012, 05:13:28 pm »
i have a possible major bug to report

it's been happening more often than not - enough to become a major source of frustration (it really kills the let-s-go-flying vibe when you have to start all over)

the scenario is this:


airbus a330-200 by tom ruth (settings as by my post in the sharing area)

gate A-16, Lisbon intl (LPPT)

catering and boarding complete - plane very much loaded (~60% MTOW)

start pushback to the left side - release parking brakes... off we go...

apu kept on, engines not to start until after pushback (if only :P)

the truck slows down, and enters the turn, so far so good

it slows down to a halt, the wing-walker stops too...

 - now brace youselves -


the nose gear violently disassembles under the aircraft - without support, the nose ditches heavily against the tarmac

FS reports an inane "crash" - giving one's imagination free way to construe the aftermath of the "disaster"



untold amounts of shame befall my airline (yes, FsPassengers makes it look pretty serious)



if hopes of a better outcome are still larger than the level of frustration at this point, a second try follows, starting all the way back at the gate....

there are no reports of this problem upon such second attempt, which only makes it that much more bizarre  ???


still, should patience be low on supply (growing more and more usual) - a straight-away continuing of the flight is preferred, starting from the position shortly before the time of the inglorious event (i gather FSUIPC allows this in case of such ground crashes) - but only to encounter the most uncanny of problems

to everyone's dismay - the recently-reloaded plane is now incapable of moving... how? - the engines spool up, the speedometer gauges increasing velocity

the plane even tosses to and fro as if in motion...
bystanders will even spot the wheels spinning under an otherwise completely static aircraft

perplexed and confusticated, the pilot ends the flight... :o


following the incident, a bug is reported at the GSX forums....

thankfully, the pilot is not injured, and after a needed run to the supermarket will return to service later today and take on a new trip ::)



but one cannot not ever be sure the gear will remain attached until the start of taxi  :-\



cheers...


 -- edit:

 - being a fellow game programmer myself, i offer a hint towards a possible cause (which i shall investigate futher later on)

the Thomas Ruth A330 series has a distinct peculiarity in that the initial standing attitude of the aircraft (static pitch) doesn't match the resting position of the plane very precisely

this is visible in the form of a little jolt when starting a flight and sometimes when switching views while landed - the smoke rising from the tires is a clear indicator that the plane was even placed slightly above the ground....

without knowledge of the inner workings of the GSX pushback script i cannot infer as to what exactly leads this generally harmless  quirk into the ways of a brutal crash -- but my debugger sense is tingling towards it as a very probable cause
« Last Edit: May 19, 2012, 05:42:08 pm by Moach »

virtuali

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Re: pushback ends with destruction of nose gear - crash
« Reply #1 on: May 19, 2012, 07:24:41 pm »
the Thomas Ruth A330 series has a distinct peculiarity in that the initial standing attitude of the aircraft (static pitch) doesn't match the resting position of the plane very precisely

This is visible in the form of a little jolt when starting a flight and sometimes when switching views while landed - the smoke rising from the tires is a clear indicator that the plane was even placed slightly above the ground....

I think you already suspected what the problem might be, and it's not a GSX problem. What might seems an harmless glitch in normal taxiing, might be enough to trigger a crash when pushing back.

Since you will surely confirm this only happens with that specific airplane, the only solution is to fix that airplane, to have correct contact points, static_cg_height and everything else that might affect its ground stance.

Moach

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Re: pushback ends with destruction of nose gear - crash
« Reply #2 on: May 19, 2012, 10:58:22 pm »
will try - i'll let you know how it goes ::)

Moach

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Re: pushback ends with destruction of nose gear - crash
« Reply #3 on: May 19, 2012, 11:12:39 pm »
fixed!

for anyone having similar problems, this is the revised .cfg settings used to eliminate the "jolt" bug with this aircraft:

static_pitch = -1.25
static_cg_height = 17.0

just replace those lines in the aicraft.cfg, they're located right under the contact points section ;)