Virgin Windshear Incident VHHH
Thread Starter
Joined: Jan 2005
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From: Ask Crew Control
Virgin Windshear Incident VHHH
Hello,
I was wondering if anyone knew of any links to information regarding the Virgin 340 that encountered severe windshear on approach to Hong Kong back in 2002. I am very new Airbus pilot in Hong Kong and felt it would be a useful read.
Thanks,
The Cav
I was wondering if anyone knew of any links to information regarding the Virgin 340 that encountered severe windshear on approach to Hong Kong back in 2002. I am very new Airbus pilot in Hong Kong and felt it would be a useful read.
Thanks,
The Cav
Joined: Mar 2006
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From: TLV
I have some written report of an a340 windshear incident in HKG, didn't realize it was Virgin.
What I remember is that there was a typhoon some 200nm away, and windshear alearts were present, extra fuel uplifted.
The first approach was abandoned because of a windshear encounter at some 500'.
After some time in the hold, a second approach was started.
The tower issued a windshear alert of -25kt at 3 miles.
Now you have to know the LLWAS system in order to understand what happened: the systems gives out first-encouter-max-strength alert, which means if you have a medium shear at 3 miles and one more severe at 1 mile, you will get the alert that the crew got.
Sure enough, the encountered some shear at 3 miles, but it was moderate and the approach continued, believing they had passed the reported shear. Then at some 300', they encountered the big one.
The captain, who was the PF, executed a recovery maneuver (as far as i know a340, its just pullng all the way back and opening max power), and they recovered at 80' AGL, and diverted to their alternate.
This is just from memory, I will have access to the full report when I get back home in a few days.
What I remember is that there was a typhoon some 200nm away, and windshear alearts were present, extra fuel uplifted.
The first approach was abandoned because of a windshear encounter at some 500'.
After some time in the hold, a second approach was started.
The tower issued a windshear alert of -25kt at 3 miles.
Now you have to know the LLWAS system in order to understand what happened: the systems gives out first-encouter-max-strength alert, which means if you have a medium shear at 3 miles and one more severe at 1 mile, you will get the alert that the crew got.
Sure enough, the encountered some shear at 3 miles, but it was moderate and the approach continued, believing they had passed the reported shear. Then at some 300', they encountered the big one.
The captain, who was the PF, executed a recovery maneuver (as far as i know a340, its just pullng all the way back and opening max power), and they recovered at 80' AGL, and diverted to their alternate.
This is just from memory, I will have access to the full report when I get back home in a few days.
Thread Starter
Joined: Jan 2005
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From: Ask Crew Control
From what I heard they went to selected speed on the approach to avoid a flap overspeed, and as soon as they went managed speed with the engine spooling down the windshear encounter occured.
If you could find the report I would appreciate it.
Thanks,
The Cav
If you could find the report I would appreciate it.
Thanks,
The Cav
Joined: Jun 1999
Posts: 978
Likes: 1
From: In the SIM
Cav,
I suggest you get as much information as you can, some of your approaches in those strong southerly winds always left much to be desired.
You not flying a terror hawk now
.
See you in November for more funny stories, have a few to tell myself now
.
I suggest you get as much information as you can, some of your approaches in those strong southerly winds always left much to be desired.
You not flying a terror hawk now
.See you in November for more funny stories, have a few to tell myself now
.
Joined: Oct 2004
Posts: 916
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From: Near sheep!
From what I heard they went to selected speed on the approach to avoid a flap overspeed, and as soon as they went managed speed with the engine spooling down the windshear encounter occured.
Joined: Aug 1999
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From: Dublin, Ireland
I was always under the impression (clearly wrong, based on the above!) that in the event of windshear, the aircraft itself would initiate a go around, rather than the crew - or is there a mode in which this would be the case?
In a situation like the above, where the aircraft meets windshear and "decides" to go around, can the crew override this without risking the same incidents which befell the Interflug A310/CAL A300-600, a few years back? (Different cockpits, I know and I can't recall any situation where something similar has happened on the full FBW aircraft, but just curious.)
In a situation like the above, where the aircraft meets windshear and "decides" to go around, can the crew override this without risking the same incidents which befell the Interflug A310/CAL A300-600, a few years back? (Different cockpits, I know and I can't recall any situation where something similar has happened on the full FBW aircraft, but just curious.)
Joined: Jun 2001
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From: Blighty
The aircraft won't initiate a go around for windshear. It gives the crew a warning of windshear if it is encountered, or of windshear ahead if Predictive Windshear is fitted. The crew can make a decision baed on the information.
What you may be thinking of is Alpha Floor Protection. This is a function of the protection systems and it triggers if the speed is significantly below the Alpha Floor Protection speed which is computed by the Flight Augmentation Computer and is based on angle of attack. If it triggers, the AP/FDs will initiate TOGA and the thrust goes to TOGA regardless of the Thrust Lever angle. It can be disengaged by swtching off the FDs and/or disengaging the AP. However, the thurst goes into TOGA Lock and can only be disengaged by deselecting Autothrust.
What you may be thinking of is Alpha Floor Protection. This is a function of the protection systems and it triggers if the speed is significantly below the Alpha Floor Protection speed which is computed by the Flight Augmentation Computer and is based on angle of attack. If it triggers, the AP/FDs will initiate TOGA and the thrust goes to TOGA regardless of the Thrust Lever angle. It can be disengaged by swtching off the FDs and/or disengaging the AP. However, the thurst goes into TOGA Lock and can only be disengaged by deselecting Autothrust.
Joined: Sep 2006
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From: UK
I haven't found any official report online (unsurprisingly for China), but try these, maybe?
"Weather on Wings" - Newsletter for the Aviation Community, by the Hong Kong Observatory:
http://www.hko.gov.hk/publica/wxonwi...018/wow18e.htm
"Windshear & Turbulence in Hong Kong - Information for Pilots":
http://www.weather.gov.hk/aviat/arti...et-web-ver.PDF
Happy landings!
