S76 TV Tower in Istanbul/Turkey

[skadi]

At least 5 of 7 POB were killed when a S76 collided with a TV Tower in Istanbul 5 minutes after takeoff in dense fog.

http://www.mirror.co.uk/news/uk-news/istanbul-helicopter-crash-least-five-10001031

skadi

[bgbazz]

This is how they reported it here...

Istanbul helicopter crash: At least Five Dead - Novinite.com - Sofia News Agency (http://www.novinite.com/articles/179172/Istanbul+helicopter+crash%3A+At+least+Five+Dead)


RIP.

[Tetsuo]

Pictures of the crash site below.

Büyükçekmece'deki helikopter kazas?n?n ard?ndan ilk foto?raflar - Foto?raf Galerisi - T24 (http://t24.com.tr/foto-haber/buyukcekmecedeki-helikopter-kazasinin-ardindan-ilk-fotograflar,6204)

[Spunk]

Elevation at the Endem TV tower: 193 m
The tower itself has a height of 236 m. There is a visitor area between 148 to 160 m.

[skadi]

Crash was recorded by a nearby CCTV

https://youtu.be/72a3WLSbk-I

72a3WLSbk-I

skadi

[2016parks]

That tower seems to be over 10 miles from the Ataturk airport (their reported departure point). Is 700' AGL appropriate at that location? It is an urban area.

[whoknows idont]

Is 700' AGL appropriate at that location

I think the outcome is testament to the fact that 700' was in fact not appropriate. :(

[SASless]

Actually...height alone is not the criteria..

In this case just as in the London 109 Crane collision proved....track and height combined with visibility determines appropriateness.

[Winnie]

How did ANYONE on board survive that...

[212man]

How did ANYONE on board survive that...
I'm assuming it was early reporting and only 5 confirmed. Can't believe anybody survived.

[Michael Gee]

Reported as being Foggy - Many pictures show otherwise!
Would local radar not have seen what was about to happen and issued a warning.

[skadi]

Reported as being Foggy - Many pictures show otherwise!
Would local radar not have seen what was about to happen and issued a warning.

These were the conditions right after the crash

http://media-cdn.t24.com.tr/media/sets/6204/uncut_page__429790887.jpg

skadi

[Ascend Charlie]

There was a bit of a breeze blowing - watch the smoke from the crash - and from my met theory from 1970 I understood that fog won't form in a wind.

So maybe this is low cloud blowing onto the hills, and the lazy ground-based reporters called it fog?

[SASless]

Fog or low cloud....with poor visibility.....are ignoring the simple fact it was the lack of being able to see and avoid the obstacle that is most likely cause based upon either the official forecast or the photo's being posted.:rolleyes:

[Keke Napep]

There was a bit of a breeze blowing - watch the smoke from the crash - and from my met theory from 1970 I understood that fog won't form in a wind.


I guess you never learned about advection fog or frontal fog then? The official definition of fog is just horizontal visibility of less than 1,000 metres (0.54 nm) caused by water droplets suspended in air, from what I learned in met theory

[[email protected]]

keke - AC was referring to radiation fog with his comments about wind - I think you'll find he knows plenty about the other forms.

[nowherespecial]

MG - Istanbul Ataturk does not allow IFR rotary traffic so this ac would have been flying VFR, in theory along a set route and thus collision information unlikely to be passed.

[Michael Gee]

Nowherespecial.
Should it have been allowed to take off then. Maybe out of limits but may have had SVFR approval if on approved low level route. Surely the Local radar would have all A/C on the screen and seen what might happen. My View.

[212man]

Nowherespecial.
Should it have been allowed to take off then. Maybe out of limits but may have had SVFR approval if on approved low level route. Surely the Local radar would have all A/C on the screen and seen what might happen. My View.
I don't think the ATC would have been paying much attention to it, from the little I know of helicopter ops from that airport.

[nowherespecial]

The area to the North of IST is very much different from the environment at IST. About 5km north you have rolling hills up to about 700' AMSL (IST is about 10' AMSL) with dense vegetation and forests. It absolutely 100% has it's own microclimate there. If they have no specific weather info from the area north of IST (and there are no airfields there so there is nothing accessible) then I suspect you could easily find suitable weather to launch at IST and a situation not close to being VFR in the region to the north.

IST is one of the world's busiest airports, a FW ac departs there every 50 seconds and lands on a different runway at roughly the same interval. The controllers hate RW traffic there as it interferes with the FW too much. From memory there is a speed restriction coming in of about 160kts minimum, hence no IFR for RW. Basically once the RW depart the ramp up by the VIP/ GA terminal, no one cares what you do and no one is really watching, certainly not in real time.

Just my experience of the area though.

[Sir Korsky]

If they were doing 140 knots plus, which was probably very likely, that kind of viz is deadly as things happen quickly. Customer pressure was more than likely the defining cause. They probably just elected to carry on at full speed instead of selecting IAS, slowing up to 90 knots and moving to plan B or C. That aircraft more than likely had GPWS too, probably with the call outs silenced. Bring on the drones.

[Michael Gee]

Nowherespecial.
This 76 was heading West ! 6 NM from IST

[nowherespecial]

The ground is higher there too, albeit not quite as high as to the north.

The major problem in that sector to the west is that the VFR routes require you to be above a certain height because the 2 inlets you fly over (check google - line straight from the North side of IST to the crash site) are also bird sanctuaries.

So..... if ATC are pushing you up to run in the scud at the cloud base to avoid the birds, inadvertent IMC comes into play. Likewise if it's bird migration season (no idea my end of if is or not), then potentially a large flock from the sanctuary might have an effect, either by bird strike or by contributing factor in some way.

Not nice any which way. RIP.

[Mast Bumper]

Having flown in the IST area for a few years, I can confirm everything that nowherespecial is writing.
Based on the official information so far, I would say this fatal accident is a very close copy of London a few years ago. Along the route the helicopter took there is a large area of heavy construction with lots of cranes and new buildings. I could see how the pilots were being pushed higher and higher to remain clear of these obstruction, to an altitude were they had very limited visibility horizontally, but were still able to see what's below them. The radio tower that they subsequently hit appeared out of nowhere. In this scenario, high speed leaves little margin.

[OttoRotate]

Airframe 760749 was a DVIP configuration delivered to Eczacibasi from Coatesville around 2008. The current CEO was among the passengers.

As for cause, this tower is comparable in size to the Seattle SkyNeedle. I would imagine visibility would have to have been compromised.

Does the state of the tail section give any clues? It looks to have sheared cleanly right at the transition behind the engines. Could this be indicative of a broadside collision? Maybe they went hard pedal in a last moment reaction.

[gulliBell]

I doubt very much that you could get an S76 broadside at 140 kts with the hardest of hard pedal. That tail boom looks cut about where the MR might swing down and chop it cleanly off.

[hihover]

Sir Korsky, you should become an accident investigator. Your insight is truly amazing and is wasted if you do not offer your services to the NTSB or similar. Well done for putting that scenario together.

Now all we need to do is get rid of the "ifs", "probablies" and "likelies". But they're not that important if you've already figured out the scenario.

Listen to yourself ffs. There are people dead here and you are making stuff up.

Tam

[Sir Korsky]

Yes Tam, it is harsh, but the kind of behavior suggested is common place and I see it far too frequently. Anyway, back to your Scotch and your fireplace Tam. I think it's snooze time again dear. Anyway, looking at the plummeting video, looks like a blade strike.

[hihover]

I think a blade strike is pretty likely if he hit that tower.

No Scotch, don't like the stuff, but a Cognac will go down nicely. Good idea.

Tam

[Sir Korsky]

https://www.youtube.com/watch?v=jjoNb9Q3r9Q

Mid air blade strike from the past. Some similarities.

[Bosphorus]

No common clue for a direct blade strike on the tower. Most Probably they saw the tower in the last second and a very small hit was enough for all of the blades spread away around. Two blades of the four were found in a perfect condition just in the bottom of the tower.

[Bosphorus]

The problem here is the VFR routes combined with bad weather. The Victor apron (used by helicopters ) for Atatürk Airport is located in the West. So in any case, regardless of your flight plan, you have to fly away 10 miles to the west, following the VFR routes, not to the North. And that tower is located in the middle of that WEST VFR route with 1100 feet AGL(İmagine a tower on a hill) There is only very small margin of 300-400 feet, taking into consideration that it is not allowed to fly above 1500' for VFR traffics inside İstanbul TMA.So when you combine the route with bad weather, just consider the microclimate conditions occurring over the hills, it's just a bit of perception of crew which were forced to fulfill the job given by.
One last word, it was not the fog, it was the haze together with the rain. This is why the visibility was 4km on the ground but getting worse with climbing.

[Bosphorus]

By the way;
When i look above, i just see the suggestions, speculations, likelies, recommendations and evaluations.
There is no RIP or condolances stated except nowherespecial and Tam.
It's not a video game or FFS flight, it's the reality. There is no difference with S-92 crash happened just several hours.
We lost seven people in this accident. And the two pilots were really well trained aviators.
Please try to be more human.
There is only one world we stand on it together and the air is the same we fly through.

[Sir Korsky]

And the two pilots were really well trained aviators.

There's no denying that - but I'm sick of reading these kind of accident reports. Most of the time, good guys got pressured into making flights or continued when they knew deep down it was wrong. Look at the Korean S76 accident. Very similar scenario.

http://www.pprune.org/rotorheads/527900-s76-down-seoul-korea.html

My condolences to all.