Ash Cloud Damage
 

So what's the truth in the rumor that 4 virgin aircraft grounded due ash cloud leading edge damage. I heard the engineers were pissed that they had to do a boroscope inspection for the engines.

None of this ever makes the news but lucky virgin kept flying.

Ash Cloud Damage
 

Not luck, but sensible and safe Flight Operations & Maintenance.

Nil Damage Evident.

what are they doing flying near the ash cloud putting the travelling public potentially at risk - not to mention the shareholders..

This is why it's called Pprune! Nothing like rumours.

TBM legend, what ever?

TBM,

Just like every other operator, (except the QF group and Tiger) it was safe to fly.
More airlines found it safe to fly provided the required separation (vertical or horizontal) was followed.
Not one airline (including Virgin) has found an sign of ash damage on any aircraft.

TBM- Legend..... You accept the substantial risk of flying a single engine turbo prop IFR at night over tiger country don't you? One assumes you've made the risk assessment and come to a safe decision regarding the above. So don't criticize others for doing the exact same thing mate.:D

Hmm. Fly a turbo prop with a known maintenance history at night or fly under a cloud of ash of unknown density and base of unknown height- except based on computer models. I know which I'd pick.

Source? Evidence?

Exactly my question. But from the responses looks like more rumor than anything else.

Standard qantas response hey keg????

The density has absolutely no relevance if you are not in the affected airspace.... The modeling accuracy wrt the altitude of the cloud is quite high hence the risk assessment conducted by every airline that flys into Australia except Qf and tiger, allowed for continued operations.

But hey what would airlines the likes of Cathay, emirates, ethiad, south African, Singapore, Malaysian, united and virgin know.......

An interesting point of note on day 2 of the ash saga.. Was operating a service hba-syd at 180 below the forcast ash area and observed a contrail well above our level. Atc when quieried, advised that it was a Qf 737 operating in the ash advisory area at 320..... I guess qantas must have knowledge the rest of the universe doesn't.......

Standard QF response campdoag? Nothing else I post on PPRUNE is normally 'standard Qantas response'- and a reading of many of my previous posts would tend to confirm that I have no qualms with sledging QF if it's deserved- so I'm not going to start with this issue.

However, an 'appeal to authority' and the fact that SQ, CX, EK, etc are all flying doesn't do much for me. I'm sure we've all got examples whereby other airlines did things that we all found strange- you quoted one in your post. SQ attempted to take off in Taipei one night when others were saying 'no' and look how that turned out. I've watched SQ (and others) disappear into massive CBs ex SIN too but that doesn't mean that it's 'safe' to fly.

Perhaps other airlines have more info that QF have- wouldn't be the first time. Based on my reading of the issues though- and not just based upon what QF tell me- I can only say that the prospect of flying under an ash area of unknown/forecast base and unknown/ forecast concentration doesn't fill me with the warm fuzzy feeling that I like to have whenever I go flying.

A couple of other points. The density has direct relevance if you fly into it. If you're basing your flight on flying at FL230 because the models say the ash is all above FL300 then that's your call. The question is though, how do we treat forecasts of turbulence? With scepticism? Do we think that because the forecast says that the turbulence is FL280 to FL350 that we can't get 'bounced' at FL250 (or below) or above FL350 due to the same 'system' that is causing the forecast area from 280-350?

For me, I'm glad that QF made the decision not to fly. It saved me from having to do a LOT more work to ensure that the decision made by office whallahs wasn't going to impact on the person who actually has the legal responsibility for the flight- IE, me.

That's your choice Keg man :)
CX has extensive history flying in areas of ash clouds all over the world as it effects some part of our network somewhere most days.
Seems the proof of the pudding is in the eating and as of now not one single RR Trent in our 330 fleet has evidence if Ash ingestion after flying below the ash area in Oz.

Not that I'm saying QF were wrong, just that their risk assessment ( probably helped along by GE RR PW and your leasing companies ) decision was not to fly. QF's choice but at the end of the day it COST QF a lot of dollars to stay on the ground when it appears the ash models were correct and if anything very conservative.

buffers on ash forecasts
 

From a long discussion with VAAC a while ago they indicated additional buffers should not be put on their forecasts as they already include significant amounts of spare space.

:ok:

Ok. Just went down to the engineering hut in MEL and asked. Complete bullocks. One aircraft had what looked like some evidence but turned out just bugs and normal dust.

End of thread fellas. FFS.

Its a computer model - which is an educated guess.

Just like your inter thunderstorms on the TAF.

Or when you turn up and the weather is not as forecast.

I'm with you Keg.

It's computer predictions based on Multi Spectral Satellite techniques, it's continually updated and not a guess at all.

I'm sure most of you would have seen this:--

BoM-Darwin Volcanic Ash Advisory Centre

I'm a bit more of a cynic.

I believe the QF group and Tiger did not fly for reasons political more than anything else.

They each have some hot potatoes with the local regulator and some senators that other very experienced airlines do not. They simply did not want the heat that would inevitably come with an aircraft that suffered any ash damage whatsoever.

If it's not a 'guess', then why are these shapes so indistinct?

I'm sure the airlines get much more accurate information and with smaller time frames between decision to enable decisions on an hour by hour basis about where the ash is and at what levels.

I'm agreeing with Waren9 on this one. With Tiger's "show cause" recently & Qantas' track record on maintenance these least few years, I'm quite certain it was politically motivated. Unfortunately, Qantas is on the way out.....

The threat with a low-density cloud is the potential maintenance cost; not crashing. Inspections – possible maintenance – and servicing is needed for aircraft that fly through an actual or forecast ash cloud (low density clouds may not be visible).

Air New Zealand dodged the forecast areas and monitored their aircraft – the Chief Pilot said their was no evidence of ash ingestion.

I was told by a pilot that Air New Zealand was getting better than public information about the position and height of the cloud, and the methods used were reliable – it seems to have worked, and their customers are happy.