Superjet crashes on demo flight in Indonesia?

[onyx39]

Just seen this on twitter...

http://www.bbc.co.uk/news/world-asia-18004097

[phumy]

Im in West Java now and saw this on BBC News, theyve called off the helicopter search at darkfall, which was about 2 hours ago here.

[bob1179]

Not much news seems to be about regarding this. It appears the aircraft was on a demonstration flight.

Due to the aircraft being flown in hilly terrain, could it simply be a case on the pilots flying into high ground? It was a brand new aircraft and the Russians do have a tendency to show boat.

[Godalmighty83]

Was linked to a Russia Today release (which are usually hilarious propaganda) that definitely mentioned the plane possibly dropping to 6000ft in an area containing peaks well above that, they went on about suspecting hijacking etc.

[mosc7pc2]

BBC breakfast says one of the rescue helicopters spotted the wreckage. Sad times.

[bob1179]

A lex said:

Looks all the world like CFIT.

What a shame!

This is what I'm thinking. Russian pilots enjoy show boating, especially with some potential customers on board their spangly new jet plane.

Without wanting to jump to assumptions, I reckon they were giving the customers a bit of a thrill ride and it went pear shaped.

[garos]

bob1179 said:

A lex said:

Looks all the world like CFIT.

What a shame!

This is what I'm thinking. Russian pilots enjoy show boating, especially with some potential customers on board their spangly new jet plane.

Without wanting to jump to assumptions, I reckon they were giving the customers a bit of a thrill ride and it went pear shaped.

8 pilots onboard, so yeah quite possibly the one in the seat trying to show what he could do.

Good news, if there can be any, is that it seems there were less people onboard than initially thought as some got off prior to take off, how must they be feeling.

[Vieste]

Volcano got in the way.

[Aspect]

Jesus, clip it within about 10 meters then have a vertical drop.

[Aspect]

It looks to have squareish windows on the nose. I thought the world established this didn't work with the Comet...

[Hooli]

Aspect said:

It looks to have squareish windows on the nose. I thought the world established this didn't work with the Comet...

I don't think that was the cause of the crash, besides aren't cockpit windows squareish on most aircraft?

[FourWheelDrift]

BBC said:

At 14:50, it was recorded as dropping from 10,000ft [3,000m] to 6,000ft near Salak, a peak measuring 7,200ft (2,200m).

Reuters via National Post said:

Transport ministry spokesman Bambang Ervan said the plane was flying at 10,000 feet and asked for permission to descend to 6,000 feet. “The last contact was when they asked for permission to descend from 10,000 feet to 6,000 feet,” Ervan said.

http://news.nationalpost.com/2012/05/09/russian-su...

If given permission to descend to 6,000ft near a mountain 7,200ft high then someone screwed up badly.

[Starfighter]

Hooli said:

Aspect said:

It looks to have squareish windows on the nose. I thought the world established this didn't work with the Comet...

I don't think that was the cause of the crash, besides aren't cockpit windows squareish on most aircraft?

The problem is not the square shape as such but the radius in the corners creating the stress raiser and allowing the crack to propogate.

[Hooli]

Starfighter said:

Hooli said:

Aspect said:

It looks to have squareish windows on the nose. I thought the world established this didn't work with the Comet...

I don't think that was the cause of the crash, besides aren't cockpit windows squareish on most aircraft?

The problem is not the square shape as such but the radius in the corners creating the stress raiser and allowing the crack to propogate.

Rings a bell from things I read years ago.

[bob1179]

The early Comet aircraft failures were caused by the design of the cabin windows and antenna windows in the roof. These acted as stress raisers and caused failures in the aircraft skin that propagated between the two roof windows, around the fuselage and along the top of the cabin windows causing structural failure.

The designers had originally wanted smaller rounded windows, however it was insisted that the windows be big and square to offer a good view and emulate those of a liner.

[FourWheelDrift]

Cracks were caused by riveting the very thin window aluminium frames to the very thin aluminium body skin when the design had originally specified glue. There were no holes pre-drilled so the the impact of the rivet going through the aluminium caused tiny cracks emanating from the hole which got longer during the pressurisation/de-pressurisation cycle until causing failure.

[Moose.]

A lex said:

At the end of the day its always the pilots responsibility to ensure the ultimate safety of his aircraft and not ATC.

Yup! And if you've ever flown in Indo you'd know to take pretty much anything ATC tell you as a potential threat.

[Eric Mc]

FourWheelDrift said:

Cracks were caused by riveting the very thin window aluminium frames to the very thin aluminium body skin when the design had originally specified glue. There were no holes pre-drilled so the the impact of the rivet going through the aluminium caused tiny cracks emanating from the hole which got longer during the pressurisation/de-pressurisation cycle until causing failure.

Exactly. The "squareness" of the apertures wasn't really the issues, more the lack of stress relief techniques being used in the corner sections of each aperture.

Most jet airliners built since the Comet have had "squarish" shaped windows of some sort or other - but the corners have been properly radiused and other stress relieving techniques have been incororporated in the overall design.