Airlander incident.

[anonymous-user]

As above, how is Buoyancy and Trim managed in this thing? and how fast can it be modified? Presumably not fast enough to avoid a large chunk of Bedfordshire coming up rather too fast in the windows.......


iirc, NASA Dryden lost one of their active stability demonstrators in the early 70's on a very early test flight (2nd or 3rd flight) because the elevator PFCU had been connected backwards

[Gretchen]

They made a man made pool to fly SkyCat over and land on

[Composite Guru]

I did my work experience at Airship Industries in 1990 and the way the attitude and trim was controlled was with two big internal air sacks inside. If you wanted nose up you pumped air into the rear sack and if you wanted nose down you pumped air into the forward sack. If you wanted it to go higher you defalted both, if you wanted to land they filled them up. It all to do with the displacement of the helium really. The fins were used just for yaw and up and down trim.

[Eric Mc]

Gretchen said:

Eric Mc said:

Are you referring to the financial state of the Zeppelin company - or some other airship operators?

The Cardington based companies. Airship Industries, ATG, SkyCat etc.

See my comment above about British companies. The other operators of airships seem to have found a niche where they CAN operate them effectively and economically.

[Gretchen]

Eric Mc said:

See my comment above about British companies. The other operators of airships seem to have found a niche where they CAN operate them effectively and economically.

Not with the same technology though? Bullet proof, military cargo carrying, unmanned and airborne for weeks at a time?

[Robertj21a]

According to the BBC, an electricity company has said that it DID come into contact with high voltage power lines.

[Gretchen]

Robertj21a said:

According to the BBC, an electricity company has said that it DID come into contact with high voltage power lines.

They've released a statement to apologise but said this wasn't cause for the heavy landing.

[hidetheelephants]

Composite Guru said:

I did my work experience at Airship Industries in 1990 and the way the attitude and trim was controlled was with two big internal air sacks inside. If you wanted nose up you pumped air into the rear sack and if you wanted nose down you pumped air into the forward sack. If you wanted it to go higher you defalted both, if you wanted to land they filled them up. It all to do with the displacement of the helium really. The fins were used just for yaw and up and down trim.

Do they have equipment to compress the helium or does it just get vented?

[Boatbuoy]

The helium volume remains within the envelope. By inflating the 'sacks' or ballonets as they are called, with air the helium is compressed within the confines of the envelope. It's much like the buoyancy or ballast tanks in a submarine.

[Composite Guru]

Boatbuoy said:

The helium volume remains within the envelope. By inflating the 'sacks' or ballonets as they are called, with air the helium is compressed within the confines of the envelope. It's much like the buoyancy or ballast tanks in a submarine.

Yeah that's right.

Also the Helium in the Envelope is passed through a purifying system in the hangar to remove any impurities from the gas. Not sure if this is the same system they use in this one.

[anonymous-user]

Boatbuoy said:

The helium volume remains within the envelope. By inflating the 'sacks' or ballonets as they are called, with air the helium is compressed within the confines of the envelope. It's much like the buoyancy or ballast tanks in a submarine.

And what rate of change of buoyancy does this system deliver? Air is relatively light, so you have to move large volumes of it to make significant buoyancy changes surely? (unlike a submarine that operates in nice dense water).

[Caruso]

I was impressed that nobody was hurt, having seen the damage to the cockpit.

But it looks like the accident was slow enough and there's enough room in the cockpit to walk away from the accident.

[eltawater]

She's gone back into the hanger now. So either it'll be a winter of repairs / redesign or it'll be the sad decommissioning.

[hidetheelephants]

If it takes 6 months to carry out £20k of repairs to the gondola their business model has other problems.

[RobDickinson]

hidetheelephants said:

If it takes 6 months to carry out £20k of repairs to the gondola their business model has other problems.

Its not exactly a production line thing.

£20k wouldnt do much to fix a car let alone a development aircraft like this

[anonymous-user]

From the footage/images i've seen i'd expect most of the gondola to be scrap tbh! It looks like it's fibreglass and has pretty much been snapped in two. And probably wrecked a lot of the instrumentation/flight controls too as it's broken.

Be amazed if it's flying in less than 6 months, especially as they need good weather to fly, so winter isn't ideal for flight tests.......

[anonymous-user]

Eric Mc said:

bulldong said:

I am pretty sure they use them for tourism only.

That's a perfectly valid use of them, isn't it.

Don't be so pedantic, you must be able to see my point. Limited tourism flights could hardly be described as a runaway success though can it? Even if they work, they're pretty much completely useless. I am astonished that anyone would look at an airship and say "that's a brilliant use of £25m".

[Pupp]

It'll be back soon enough; it was just a bli(m)p...

[hidetheelephants]

Edited by hidetheelephants on Monday 29th August 08:32