Helicopter - v - crane LONDON

[ShyTorque]

Thankyou BOAC I did look and saw that you have now amended your profile from simply "UK".

Apart from that, thanks again, you obviously went to some trouble to fully reinforce the main point raised in my latter paragraph!

-----------------------------

I'm obviously no expert to someone of your all-knowing magnificence, and never could be, for daring to try to explain something to you about how helicopters are operated on the helicopter routes, over which you appeared to have some confusion. My apology, I won't try such a thing again.

However, to show just how thick-skinned and stubborn I can be, please deign to allow me to put forward a probably feeble but well intended attempt to answer SASless's earlier question about the A109E and icing conditions:

My copy of the "E" model RFM is no longer up to date but the following words appear therein (AFAIK there has been no change to the icing clearance for the basic aircraft).

LIMITATIONS

TYPE OF OPERATION

This helicopter, in the basic configuration, is approved for operation under day and night VFR, non-icing conditions.
The IFR configured helicopter is certified for IFR operations during day and night, non-icing conditions.

SASless, hope this is of some use, me old mucker!

[nigelh]

The fact that LCY had no landings doesn't prove anything . I have often flown into LBA when there have been no landings due to weather .
I can't believe all the talk re helicopters and icing . As far as I am aware none of the sort of helis we fly have any icing capability ....only the sort of things DB shuttles out to the rigs on will have that . ( ok maybe the new Sikorsky as well )
Icing , I believe is a total red herring here . If you had a problem with it you would definitely go down , and not up ,in that situation over London .

[jellycopter]

Historical TAFs

Sarwannabe

I got these from 'ogimet' so think they are accurate. They paint a pretty good picture of expected weather around London that morning. Clearly they're not Central London, which often has slightly higher cloudbases due to its microclimate, but nevertheless do give a good idea of anticipated conditions.

JJ

GATWICK
TAF AMD EGKK 160558Z 1606/1712 07005KT 2500 BR BKN003
PROB30 TEMPO 1606/1610 0300 FZFG BKN001
BECMG 1610/1613 6000 NSW FEW015
BECMG 1618/1621 2000 BR
PROB40 1623/1710 0300 FZFG VV///
BECMG 1710/1712 6000 NSW=

TAF EGKK 160457Z 1606/1712 07005KT 0300 FZFG BKN001
TEMPO 1606/1610 1000 BR BKN002
BECMG 1610/1613 6000 NSW FEW015
BECMG 1618/1621 2000 BR
PROB40 1623/1710 0300 FZFG VV///
BECMG 1710/1712 6000 NSW=

TAF AMD EGKK 160240Z 1602/1706 VRB05KT 3000 BR FEW015
PROB40 1603/1611 0200 FZFG BKN001
BECMG 1611/1614 6000 NSW
BECMG 1618/1620 2000 BR
PROB30 1621/1706 0500 FZFG BKN001=LUTON
TAF EGGW 160458Z 1606/1706 07004KT 0100 FZFG BKN001
PROB30 1608/1610 1200 BR BKN002
BECMG 1610/1613 6000 NSW FEW003
BECMG 1618/1621 2000 BR BKN002
BECMG 1621/1624 0300 FZFG VV///=


HEATHROW
TAF AMD EGLL 160751Z 1607/1712 04004KT 4000 BR SCT002 BKN005
PROB30 TEMPO 1607/1609 0700 FZFG BKN002
BECMG 1609/1611 6000 NSW FEW006
PROB30 TEMPO 1612/1619 9999
BECMG 1622/1701 3000 BR
TEMPO 1702/1710 1200
PROB30 1703/1709 0700 FZFG BKN001=

TAF EGLL 160457Z 1606/1712 04004KT 2500 BR SCT002 BKN004
TEMPO 1606/1610 1200 BKN001
PROB30 TEMPO 1606/1609 0700 FZFG
BECMG 1609/1611 6000 NSW FEW006
PROB30 TEMPO 1612/1619 9999
BECMG 1622/1701 3000 BR
TEMPO 1702/1710 1200
PROB30 1703/1709 0700 FZFG BKN001=

TAF AMD EGLL 160240Z 1602/1706 04003KT 2000 BR SCT002
TEMPO 1603/1609 1200 BCFG BKN001
PROB40 TEMPO 1603/1609 0700 FZFG
BECMG 1608/1611 5000
PROB30 TEMPO 1611/1620 9999 NSW
BECMG 1622/1701 3000 BR
PROB30 TEMPO 1702/1706 0700 FZFG BKN001=


STANSTED
TAF EGSS 160458Z 1606/1712 06004KT 0200 FZFG BKN001
PROB30 1608/1610 1200 BR BKN002
BECMG 1610/1613 7000 NSW FEW004
BECMG 1618/1621 2000 BR BKN002
BECMG 1621/1624 0300 FZFG VV///
BECMG 1709/1712 9999 NSW FEW004=

[101BOY]

And further to the above TAFs, the Metars also paint a similarly poor picture:

Northolt

METAR EGWU 160750Z 06004KT 3200 BR OVC003 M02/M03 Q1011 YLO2
BECMG 4000 YLO2=
METAR EGWU 160650Z 05003KT 3500 BR OVC002 M03/M03 Q1011 AMB
TEMPO 2000 BKN001 RED=

TAF EGWU 160440Z 1606/1624 08004KT 2000 BR BKN003
TEMPO 1606/1609 0700 FZFG BKN001
BECMG 1609/1611 4000 HZ BKN004
BECMG 1611/1613 8000 FEW015=

Luton

METAR EGGW 160750Z VRB03KT 0100 R08/0450 FZFG OVC001 M04/M04
Q1011=
METAR EGGW 160720Z VRB02KT 0100 R08/0375 FG OVC001 M04/M04
Q1010=

Gatwick

METAR EGKK 160720Z 03004KT 0900 R08R/1400 FZFG OVC002 M03/M04
Q1010=

City

METAR EGLC 160720Z VRB03KT 0600 R09/1000 R27/1100 FZFG VV///
M03/M03 Q1012=
METAR EGLC 160650Z VRB03KT 0900 R09/0900 R27/1200 FZFG BKN001
M02/M02 Q1011=

Biggin

METAR EGKB 160720Z 07003KT 0200 R21/0500 FZFG VV/// M03/M03
Q1010=

Not much sign of the much speculated deterioriation, looks pretty poor throughout.

[A30yoyo]

A very tall recovery crane was put in place this weekend to remove the damaged crane from the accident site.
Recovery crane assembled in Vauxhall following helicopter crash | Demotix.com

They're following the operation on the tall building forum 'skyscrapercity'....there is a recent nighttime photo of the St George's Wharf tower in relation to the older Millbank tower (i.e. either side of the centre line of the Thames Heliroute in post#2536 on
One St George Wharf (The Tower) | Lambeth | 181m | 49 fl | T/O - Page 127 - SkyscraperCity

On the R&N thread on this accident there is a youtube filmed from a helicopter following the London Heliroutes (picks up the Thames at Kew Bridge ca. 12.04 minutes in, (filmed before the St Georges Wharf tower was built)) post#321 on
http://www.pprune.org/rumours-news/5...london-17.html

What height would the youtube be filmed from?

[A310bcal]

nigelh

quote:Icing , I believe is a total red herring here . If you had a problem with it you would definitely go down , and not up ,in that situation over London .

Maybe, just maybe, PB was struggling to go UP, or maintain altitude, and as a result his navigation took second place in the flying .....and he did go down!

But as the ice would have melted and there are no blackboxes to consult....perhaps as some have already hinted, we will never know. There are certainly a few contributors on here who HAVE had rotor and airframe icing, with a result where it was impossible to maintain their desired altitude.

[SASless]

Excuse me....but going UP is a very effective tactic in dealing with Icing as well as going down. As helicopter pilots we are more inclined to go lower....but that is but one answer to the question.

Going UP....over London gets a bit complicated as compared to trying to stay low.....but there are things to be run into down low....and up high too for that matter.

[deefer dog]

Fixed wing pilot here. Dealing with ice is pretty much an every day event at this time of the year for us. On my type the airplane will happily (continue*) to fly with quite a build up. (*Not tried to take off with it though - and yes it is certified for known icing).

How much ice, if indeed any, can a helicopter take before it necessitates remedial action? Practically speaking (rather than legally) is any ice too much ice on a type that is not certified for it?

[Savoia]

Deefer: I''ve found a handy article published by the Flight Safety Foundation: http://flightsafety.org/hs/hs_nov-dec90.pdf

The rotor blade icing process and its subsequent effect on helicopter performance cannot be analyzed in the straight-forward manner used to explain ice accretion on the leading edges of fixed-wing aircraft. Spanwise elements of a rotor blade, unlike the leading-edges of an airplane's wing, move through the air at various speeds.

Rotor blade icing is made even more complex by the constantly changing angle of attack experienced by the helicopter's main rotor blades in normal forward flight. These obvious and unique characteristics of the helicopter;s lifting system, combined with differing surfaces temperatures along the blades' spanwise sections and smaller airfoil thickness, make helicopter rotor blade icing complex and extremely hazardous.

A while back I recalled my encounter with the late John 'Chalky' White recounting his days test flying the Wessex in known icing conditions and he made no bones about the fact that he thought he may have embarked upon his last flight!

In relation to the above PPRuNer Cornish Jack wrote:

Re: the Wessex and icing trials - not Norway but Canada in the mid 70s the A&AEE winter trials included a quadruple prismatic camera filming the rotor blades in flight. The movements recorded caused not a little 'interest' and one comment to the effect that "had I known that was what was going on I'd never have set foot in the thing!" Remarkably robust bit of kit!

You may also find the following of interest:

http://www.pprune.org/rotorheads/405...ditions-3.html

http://www.pprune.org/rotorheads/240...mitations.html

http://www.pprune.org/rotorheads/605...elicopter.html

[sycamore]

Have a look at `rotorheads around..cockpit views(not videos),page 15 .
Sav; I think Chalky may have been talking(as only Chalky could !) about flying a Seaking in icing near Ottawa and it lost all transmission oil; everyone had chutes on,but they got back to base OK.
If you want a helo to have a clearance to operate in icing,it has to be `designed` in properly,not as an add-on,or `maybe we can do just a bit of icing`; you must have heated main and tail rotors,a properly heated engine intake system,engines that are /have a `robust first and second stage compressor(centrifugal),and heated tailplane ;that needs a pretty big electrical supply,and redundancy.....Sorry for the drift,or `slide` in this weather...

[John R81]

Deeper dog

Helicopters are not like fixed wing in ice. Suppose you get just a little ice on rotors, the degradation to flight performance is more then for a fixed wing. Suppose the rotor sheds a little ice - not like a fixed wing where this could be good news. The FOD can impact other important things at high speed - main or tail rotors. Also, due to that shedding you may have an unbalanced rotor which can cause extreme vibration, to the extent of causing damage.

[500e]

Crane pictures
http://www.demotix.com/news/1738970/...#media-1738959

[Grenville Fortescue]

Originally Posted by Agaricus bisporus

I can just see how a guys professionalism would make him vulnerable in such a situation.

Saving been forced into a diversion in low cloud and vis you'd be doing all you could to stay as high as poss to avoid both obstructions and excessive noise. It is almost a reflex response to fly as high as you can in such a situation. And pinching it at cloud base is just where you lose forward vis while keeping ground contact, so if there's a crane jib lurking in the cloud that's just where you don't want to be. I wouldn't be surprised that if he'd been a couple of hundred feet lower he'd have had sufficient vis to see and avoid. We just don't think of obstructions growing out of cloud when you can't see an obvious base.

IMHO this talk of enhanced lighting is a red herring and would achieve little or nothing if this event was rerun. Lighting is fine in VMC but pointless if shrouded in cloud.

Sadly it looks like an unfortunate operational accident and rushing into legislatative changes is almost certainly going to be a waste of time.

Questions will doubtless be asked re the wisdom of using battersea as a diversion in such conditions given the atrocious conditions at LCY, and even that of setting off from to elstree in the first place, but that's AAIB territory.

We all know the picture when grubbing along in low cloud/vis, and with obstructions close alongside the route extending up into the clag one is in a vulnerable position.

Very sad.

Tend to agree.

[MightyGem]

Helicopters are not like fixed wing in ice. Suppose you get just a little ice on rotors, the degradation to flight performance is more then for a fixed wing. Suppose the rotor sheds a little ice - not like a fixed wing where this could be good news. The FOD can impact other important things at high speed - main or tail rotors. Also, due to that shedding you may have an unbalanced rotor which can cause extreme vibration, to the extent of causing damage.

And yet, IIRC(it's been 16 years) the Lynx was cleared up to 30mm of clear ice without heated blades.

[handysnaks]

MG. That's because the thing felt like it only had three blades fitted most of the time anyway

[A30yoyo]

View of the Vauxhall Bridge bend from the London Eye?....Westminster Bridge in foreground
St George Wharf Tower by Vaughanoblapski!, on Flickr

[sycamore]

MG ,perhaps 3 mm...

[Hover Bovver]

3mm or 30 mm, how can you tell unless you stop the blades LOL - the only reason a 109 has windscreen wipers.

[MOSTAFA]

It had an ice accretion meter (ho ho ho) still have the scars on my back 34 years later.

I seem to remember 10mm but there was something about a Q rise which meant you'd never get that far!!

[A30yoyo]

There's more high-rise planned for the Nine Elms/Vauxhall river bank area, posts #4 and #18 on
LONDON | City Tower One Nine Elms Vauxhall | 200m | 656ft | 58 fl | App - SkyscraperCity