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AirLander take off then 2nd Flight Mishap

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AirLander take off then 2nd Flight Mishap

Old 19th Aug 2016, 17:24
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I think this and future models are likely to find profitable niches. Taking heavy loads into and out of inaccessible areas is one, especially if those areas are remote. Emergency supply into areas that have suffered disruption of normal routes (earthquakes, floods, etc.) I’d have thought the much lower operating costs would facilitate everyday resupply of goods to remote communities.

Also, compared with helicopters and tilt-rotors, the concept seems inherently much safer. Lots of redundancy in the engine department and if the worst came to the worst, you just drift gently to earth. Even hitting something would probably result in a “boing” rather than a “SMASH!”.

The ratio of useful load to that of structure plus fuel appears a lot better than conventional aircraft.

Don’t discount tourism: when you see what people will pay for a small cabin in a ship that trundles around at sea level, what would they give for ever-unfolding panoramas and being able to circle places then land next to them and go and have a look? With the sort of lifting capability being discussed for the growth versions, you could fit a whole lot of luxury in there as well as a fair number of passengers...
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Old 19th Aug 2016, 17:25
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Originally Posted by Tourist View Post
4. Four weeks to wait out a storm?

That is a hell of a storm! Definitely not visiting your planet. Sounds nasty.
I would think 24hrs at 90kts will give enough radius to avoid the biggest storm on earth.
The four was a typo, I intended to type "for", as in fuel reserves for weeks. Now, that particular typo, (I'm a terrible typist) I noticed as soon as I posted that, and edited it immediately (I've edited that post a couple of times) so the only way you could have included that in my post was to have ignored the edited post and chosen to copy the text with typo unedited from your email notification of the post. Which is a a conscious act of intentional dishonesty, isn't it?

My point was that a ship carries huge fuel reserves, measured in weeks, not hours, and has great reserves over the planned consumption for the trip, so has a great deal of discretion in route modifications and diversion that an aircraft simply doesn't have.
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Old 19th Aug 2016, 17:39
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This blimp will probably contribute as much to advancing air transport as Eddie "The Eagle" Edwards did for global ski jumping.
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Old 19th Aug 2016, 17:47
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Originally Posted by A Squared View Post
The four was a typo, I intended to type "for", as in fuel reserves for weeks. Now, that particular typo, (I'm a terrible typist) I noticed as soon as I posted that, and edited it immediately (I've edited that post a couple of times) so the only way you could have included that in my post was to have ignored the edited post and chosen to copy the text with typo unedited from your email notification of the post. Which is a a conscious act of intentional dishonesty, isn't it?

I don't get email notification. I replied to what you wrote when I saw it. I don't mind you modifying your posts later, but don't expect me to mind read.

Originally Posted by A Squared View Post

My point was that a ship carries huge fuel reserves, measured in weeks, not hours, and has great reserves over the planned consumption for the trip, so has a great deal of discretion in route modifications and diversion that an aircraft simply doesn't have.
I would say that a blimp with a planned endurance of weeks has sufficient, certainly enough compared to normal aircraft that the point is invalid.
How far can an airliner go on reserves? If Airlander can go as far then you are making up problems that don't exist.
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Old 19th Aug 2016, 17:54
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Originally Posted by Scuffers View Post
Name me a large airship that has not suffered some catastrophic disaster?
1. Name me an airliner that has never crashed
2. The vast majority of the airships that you are talking about were totally different being both Hydrogen and metal structured.

Originally Posted by Scuffers View Post

Helo wise, how high do you want to go? (and to what end?)
and just how far do you need to fly? (V22 tiltrotor can do 1,000 miles)
1. Try hovering hot and high in a helicopter with a 10 ton load in one of the many countries where ground level is higher than the uk.

2.V22 is exactly the sort of niche product you decry airlander for being. Yes it goes fast but it's load is poor and it is uber expensive.

Originally Posted by Scuffers View Post
Global Hawk has something like a 40 hour on-station time, and a range over halfway round the planet.

Like I said, what's the killer-application?
Global hawk is as big and expensive and long endurance as you get, yet it carries a tiny payload in comparison, it is much more expensive and the endurance is much shorter.

Don't know about the killer app. Time will tell if there is one.
Nobody ever guesses the killer app in advance of any new technology. That's life.
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Old 19th Aug 2016, 18:13
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Originally Posted by Tourist View Post

This is what I thought until I had a bit of a think.
Why outrun anything?

What about if you just turned the engines off and drifted with the wind?
Ummm, you hit the ground, someplace slightly downwind of where you shut off your engines. I don't think you quite grasp the concept of what they're building here. The fundamental concept of this is that it's not a pure aerostat, but a hybrid, which is completely dependent on forward motion and/or directed thrust to stay airborne. That is *THE* thing which makes it different than blimps which already exist, and have very limited application. The underlying concept here (which you seem to have missed) is that it is claimed to have better lifting capabilities than blimp, is because of lift and thrust. So if you're using it to carry the loads advertised, if you shut off the engines, you come down out of the sky.

Free ballooning would certainly be an option if you were operating empty, but it's hard to make money flying around empty.


Originally Posted by Tourist
I would say that a blimp with a planned endurance of weeks has ...
But it doesn't have a planed endurance of weeks, or even one week, they suggest a loiter time of five days, but that is a max loiter time, not cruise time and not cruise time with a payload. Completely aside from the fuel/payload issue, do you really think that a heavy lift airship will also have provisioned accommodation for the crew for "weeks" ? you're drifting dangerously into Jules Verne fantasy land here.

This aircraft, like all powered aircraft is going to to be fuel and load limited. I think that you are misled by the payload and endurance figures the salesmen are slinging about somewhat carelessly. I wouldn't go as far as to say they're being dishonest, but the claims need to be taken in context. The aircraft I fly has a cruising endurance of 12-13ish hours. It also has a payload capability or about 48,000 lb. However, it does not cruise for 12 hours with a 48,000 lb payload, not even close. Payload would be less than 10,000 lb with a max fuel load. Conversely, cruise endurance with a max payload and reasonable reserves is in the neighborhood of 3 hours.

If you're using this contraption for heavylift operations you're not going be able to free balloon, and you're going to be fuel limited. You can plan on it. So you're not going to simply be able to wander off 10 hours in a new direction when bad weather is approaching, you're going to have to get yourself, and your blimp, and your heavy-lift payload on the ground, and not just on the ground anyplace, but on the ground at a location which has an airship hangar.

Last edited by A Squared; 19th Aug 2016 at 19:09.
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Old 19th Aug 2016, 18:28
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Originally Posted by Tourist View Post
What I do know is that that type of structure which is purely maintained by pressure is extraordinarily strong. I can think of no circumstance where a storm could possibly damage the basic shape through shear forces alone.
Unlike an aircraft, for example.
As far as I can see, at altitude, the threat is purely from upset of some kind due to updrafts/downdrafts affecting different parts of the envelope and perhaps rolling/pitching them. The envelope would be fine, but I suspect the contents of the gondola would get messy at that point

The danger comes if it can be forced into the ground by the weather.
During her accident-prone 18-month term of service, the Akron served as an airborne aircraft carrier for launching and recovering F9C Sparrowhawk fighter planes.

Akron was destroyed in a thunderstorm off the coast of New Jersey on the morning of 4 April 1933, killing 73 of her 76 crewmen and passengers.

This accident was the largest loss of life for any known airship crash.

In 1935 Macon was damaged in a storm and lost off California's Big Sur coast, though most of the crew were saved.
From:- USS Akron and Macon.
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Old 19th Aug 2016, 19:08
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Originally Posted by Tourist View Post
Originally Posted by Scuffers View Post
Name me a large airship that has not suffered some catastrophic disaster?

(remember what the sheds at Cardigan were built for?)
1. Name me an airliner that has never crashed.
He didn't mean that almost every airship *type* suffered catastrophe, he meant that almost every individual *airframe* suffered catastrophe. That's a significantly different proposition.
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Old 19th Aug 2016, 19:49
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Originally Posted by G-CPTN View Post
Why are you linking to stories about ridged airships with metal structures?

What relevance do these have to this discussion?
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Old 19th Aug 2016, 20:00
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Originally Posted by A Squared View Post
Ummm, you hit the ground, someplace slightly downwind of where you shut off your engines. I don't think you quite grasp the concept of what they're building here. The fundamental concept of this is that it's not a pure aerostat, but a hybrid, which is completely dependent on forward motion and/or directed thrust to stay airborne. That is *THE* thing which makes it different than blimps which already exist, and have very limited application. The underlying concept here (which you seem to have missed) is that it is claimed to have better lifting capabilities than blimp, is because of lift and thrust. So if you're using it to carry the loads advertised, if you shut off the engines, you come down out of the sky.

Free ballooning would certainly be an option if you were operating empty, but it's hard to make money flying around empty.
Nice try, but you brought up storms as a disaster scenario which would doom the airlander. Under the extreme circumstances of the 4 week storm that they cannot avoid, ditching the load is a perfectly reasonable response.

Originally Posted by A Squared View Post

But it doesn't have a planed endurance of weeks, or even one week, they suggest a loiter time of five days, but that is a max loiter time, not cruise time and not cruise time with a payload. Completely aside from the fuel/payload issue, do you really think that a heavy lift airship will also have provisioned accommodation for the crew for "weeks" ? you're drifting dangerously into Jules Verne fantasy land here.
Again, you are talking about this as if this is not the sub size prototype. They have made very clear that this is a tech demonstrator.

Originally Posted by A Squared View Post

This aircraft, like all powered aircraft is going to to be fuel and load limited. I think that you are misled by the payload and endurance figures the salesmen are slinging about somewhat carelessly. I wouldn't go as far as to say they're being dishonest, but the claims need to be taken in context. The aircraft I fly has a cruising endurance of 12-13ish hours. It also has a payload capability or about 48,000 lb. However, it does not cruise for 12 hours with a 48,000 lb payload, not even close. Payload would be less than 10,000 lb with a max fuel load. Conversely, cruise endurance with a max payload and reasonable reserves is in the neighborhood of 3 hours.

If you're using this contraption for heavylift operations you're not going be able to free balloon, and you're going to be fuel limited. You can plan on it. So you're not going to simply be able to wander off 10 hours in a new direction when bad weather is approaching, you're going to have to get yourself, and your blimp, and your heavy-lift payload on the ground, and not just on the ground anyplace, but on the ground at a location which has an airship hangar.
Neither of us have any knowledge about the truth or otherwise of their claims re load lifting capability or endurance. This is just speculation on your part.
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Old 19th Aug 2016, 20:05
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Originally Posted by Tourist View Post

1. Try hovering hot and high in a helicopter with a 10 ton load in one of the many countries where ground level is higher than the uk.
I've seen it done daily at 4000-5000 MSL in the highlands of Papua New Guinea. It was hot. And humid.
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Old 19th Aug 2016, 20:05
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Originally Posted by Tourist View Post
Why are you linking to stories about ridged airships with metal structures?

What relevance do these have to this discussion?
Probably none - my mistake.

Sorry.
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Old 19th Aug 2016, 20:05
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Originally Posted by A Squared View Post
He didn't mean that almost every airship *type* suffered catastrophe, he meant that almost every individual *airframe* suffered catastrophe. That's a significantly different proposition.
Submarines from that era had a low survival rate too.

Does that mean modern ones cannot be safe?

Passenger aircraft from that era also were not exactly safe either.

You have to compare in context, which will be tricky because there were not many helium filled airship with the shape maintained by gas pressure at the time.
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Old 19th Aug 2016, 20:09
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Originally Posted by A Squared View Post
I've seen it done daily at 4000-5000 MSL in the highlands of Papua New Guinea. It was hot. And humid.
Go on? What load and what helicopter?

50t?

I think not.

10t?

Unless it was an Mi26 I call Bullsh1t.
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Old 19th Aug 2016, 20:11
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Originally Posted by Tourist View Post


Neither of us have any knowledge about the truth or otherwise of their claims re load lifting capability or endurance. This is just speculation on your part.
Trust me, when they say payload is XX tons and endurance is YY hours They do not mean that endurance with a max payload of XX tons is YY hours. You can bet your last paycheck on it. And the figure quoted for endurance is specifically "loiter" time, whihc means only using enough power to counteract whatever wind is present. That certainly is not endurance in cruise at 80 knots.
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Old 19th Aug 2016, 20:13
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Originally Posted by Tourist View Post
Go on? What load and what helicopter?


Unless it was an Mi26 I call Bullsh1t.
Chinooks. 10T conexes. I know how much they weighed because I had flown them to that location in my airplane.
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Old 19th Aug 2016, 20:13
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I dont think so...

Originally Posted by Interested Passenger View Post
how it works

60% lift from buoyancy, 40% lift from aerodynamics, +/- 25% from vectored thrust.

I assume that's a very simplified account of what really happens - obviously at take off it can only have a maximum of 85% lift, and climbs, but in the cruise with 100% it has to stay level
and that's without mentioning the 10t of cargo it may or may not have
Only 60% from buoyancy??? Try again....
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Old 19th Aug 2016, 20:22
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Originally Posted by A Squared View Post
Chinooks. 10T conexes. I know how much they weighed because I had flown them to that location in my airplane.
At sea level, yes
Hot and High?

I think not.
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Old 19th Aug 2016, 20:23
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Originally Posted by Tourist View Post
Nice try, but you brought up storms as a disaster scenario which would doom the airlander. Under the extreme circumstances of the 4 week storm that they cannot avoid, ditching the load is a perfectly reasonable response.
Aside from the fact that an internal load is quite likely to be impossible to jettison, if your bad weather contingency plan is to simply drop the load and drift around like a balloon till the weather gets better, you've departed pretty seriously from a discussion of a practical air transport system.
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Old 19th Aug 2016, 20:28
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Originally Posted by Tourist View Post
At sea level, yes
Hot and High?

I think not.

I think so, and I've been involved in aircraft operations doing exactly that.
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