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-   -   AirLander take off then 2nd Flight Mishap (https://www.pprune.org/freight-dogs/583125-airlander-take-off-then-2nd-flight-mishap.html)

Tourist 19th Aug 2016 19:30

No, I was merely trying to point out the error in your "good luck with running away at 80kts" comment by showing that there is in fact no need to run away at all since it will drift with the weather even with no power on.

As it happens, it will be able to be 2000nm away in a day so it should not really be a problem.

Tourist 19th Aug 2016 19:32


Originally Posted by A Squared (Post 9479344)
I think so, and I've been involved in aircraft operations doing exactly that.

Boeing: CH-47 Chinook

Nope.

10.8t max.

No way no day does that equate to 10t hot and high HOGE.

vortexadminman 19th Aug 2016 19:36

I think its mint, great idea and would love to fly it. Considering all the hassle and cost of moving large bits of kit from A to B with road moves, cranes, roads, shipping costs ...... whats a day or two delay due to wind, or even a week. 5 day endurance thats not shabby.... and they have only tested that probably with FTL in mind. Good luck to them I say, we need more people giving something a shot in aviation, because there is enough saying you can't do this because ........

A Squared 19th Aug 2016 19:41


Originally Posted by Tourist (Post 9479351)
Boeing: CH-47 Chinook

Nope.

10.8t max.

No way no day does that equate to 10t hot and high HOGE.

I was flying hercs into an airstrip at 5000 ft in the highlands of New GUinea. Normally our loads were taken from the airstrip to the final destination by truck, but a landslide took out the road. For a while, the high priority items were being slung by some Columbia Helicopter Chinooks which were there operating in those oil fields. 20,000 lb was the load limit we were given for the Connexes full of high priority stuff .

I would speculate that Columbia's Chinooks were stripped of everything not strictly necessary for carrying maximum sling loads, and were lighter airframes than a CH-47 in military trim, much as our L-382's are significantly lighter than a Airforce 130H, despite being 15 ft longer. My colleagues who are former AF speak of BOWs for the C-130's almost 10,000 lb heavier than our planes. A similar thing may be in play here. Other than that, I'm done arguing with you about something I've been involved in and have seen first hand and you haven't.

Mechta 19th Aug 2016 20:52


Name me a large airship that has not suffered some catastrophic disaster?
Since Scuffers asked, how about:

Graf Zeppelin - over a million miles flown in 590 flights, 34,000 passengers carried and a round the world flight which clearly didn't have a suitable shed at each stop.

USS Los Angeles - 4181 hours, 331 flights

R100 - Transatlantic Atlantic out and return crossing

All were built before 1930, and only the USS Los Angeles used helium, so not bad for technology 86 years ago.

Its worth noting the link between the R100 and the Airlander:


One of HAV’s major shareholders is aviation enthusiast and entrepreneur Bruce Dickinson, also well known in non-aerospace circles as the lead singer of rock band Iron Maiden, who outlined the new technology used in Airlander: “Barnes Wallis’ R100 airship of the 1920s was a great design but was limited by the technologies of the day,” he explained. “The construction materials were inadequate, the engines were heavy and inefficient, flight controls were cumbersome, radar didn’t exist and navigation and weather forecasting were still at an early stage of development. In later life, Barnes Wallis wrote a note for Roger Munk, saying: ‘Solve these problems and the airship will become an efficient and viable mode of transport.’ The issues to be tackled were stability and flight control, structures, increased payload, more powerful engines, improved capabilities in poor weather and forecasting and easier ground-handling. Now we have the technology to revisit this fundamentally sound design to make it efficient and make it work.”
Its sad that Roger Munk did not live to see his dream take to Cardington skies, however I'm sure both he and Barnes Wallis would be overjoyed that the result of that conversation is now casting its shadow on those iconic sheds.

khorton 19th Aug 2016 23:14

It depends on which web site you want to believe. This site lists the max sling capacity of a CH-47D as 26,000 lb, or 11.8 tonnes.

A Squared 20th Aug 2016 00:03


Originally Posted by khorton (Post 9479536)
It depends on which web site you want to believe. This site lists the max sling capacity of a CH-47D as 26,000 lb, or 11.8 tonnes.

Sure, the thing is you can find a variety of numbers in various places. All we can say got sure is that it's apparent that the Chinook is certainly structurally capable of slinging over 10 tonne. I do know the weights of the conexes we were flying into there, and I'm fairly confident that Tourist wasn't there, flying one of those helicopters so doesn't have a point of reference what those particular airframes were capable of in that operational trim under those conditions. Anyway, the whole branch of the discussion is a bit silly and the bottom line is that there are helicopters capable of carrying a 20 tonne load, and while that capability will decrease with altitude and temperature, so too will the lifting capability of an hybrid airship which depends on aerostatic buoyancy and vectored thrust.

As far as a 50T and 100T version, they're just barely flying the 10T one so those are purely speculative at this point. I am reminded of the Moller sky car, no prototype of which has ever hovered out of ground effect, or off of a tether, but according to the promoter, is just a few years away from being able to cruise 4 people at 267 knots at 36,000 ft. :rolleyes:

When they have built one which actually *does* lift 50t, *then* we can start discussing it's merits.

It's worth noting that neither has this prototype demonstrated the ability to carry a 10 Tonne payload. All it's done is fly around empty for a half hour. So the marketing claims of "up to 10,000 kg" are just that; claims, which have not yet been demonstrated.

beamender99 20th Aug 2016 07:58

https://www.quora.com/What-is-the-ma...inook-can-lift

Boeing CH-47 Chinook

The Largest Transport Helicopters in the World - autoevolution

hunterboy 20th Aug 2016 08:20

There does seem to be a lack of imagination displayed here by some posters. I wonder what some of them would have made of the Internet 20 years ago? Mmm....a useful gadget for geeks, but where are the commercial applications?
Why don't we wait and see where it takes them? And give 'em a pat on the back for trying to be aviation pioneers again. After all, it isn't your money they're wasting is it?

Heathrow Harry 20th Aug 2016 08:23

The point is the Airlander is another take on a technology that is over 100 years old and which was kicked into the long grass over 80 years ago as a commercial failure with limited technical upside

The Internety was totally new

Tourist 20th Aug 2016 08:33

My apologies A squared, we may have been having a UK ton vs US ton issue.

20000lbs, just about squeeks in though brave pilot to ditch a 5% thrust margin in the mountains.

http://i404.photobucket.com/albums/p...hotos/CH47.jpg

Go in at 5000, lets call it 30C, and we need OGE for underslung.

So, what have we discovered?

That later developed and enormously upgraded models of one of the most impressive helicopters ever made can just about hold their own against the first sub scale prototype of a new airship over very short distances?

Not really a strong argument against the airship so far.

You query whether it will meet it's claims.

This is an argument that can be applied to any aircraft before it has been proven.

"Harrier. I don't believe it will hover therefore it will be useless" etc

To claim it is useless and has no killer application because you don't believe that it will achieve it's stated performance is very different from saying that you don't believe that even if it achieves it's stated performance aims it will have an application.

Which is it?
You seem to be pursuing both paths.

Tourist 20th Aug 2016 08:39


Originally Posted by Heathrow Harry (Post 9479772)
The point is the Airlander is another take on a technology that is over 100 years old and which was kicked into the long grass over 80 years ago as a commercial failure with limited technical upside

The Internety was totally new


What an amazing statement.

Throughout the whole history of mankind, new technologies have been trialled, failed due to materials technology and then revisited later with success.

I am having trouble thinking of any part of the Airlander which will not have benefited from vastly superior materials and technology.

JOE-FBS 20th Aug 2016 10:46

I have scanned the foregoing pages and they are full of words like guess, think and assume. May I suggest that honourable members do some research as most of their speculations are wrong. I'll provide the link below as a start. There is a huge amount of information out there.

Royal Aeronautical Society | Insight Blog | Airship resurrection

It is also worth noting that those misty eyed romantics that run Lockheed Martin are also spending money on a similar programme to HAV.

While constantly comparing HAV to the airships of the 1930s makes about as much sense as comparing an A350 to a Ju52, if you must look at history, try looking at the almost forgotten achievements of the US airship service from 1942.

Navy's Lighter-Than-Air Experience Monograph

Scuffers 20th Aug 2016 12:40

Again,

What's the killer application?

RAT 5 20th Aug 2016 13:14

Is this craft likely to be suitable for overland transport or more for oceans? For overland I could envisage desert areas and much of Africa, even N/S E/W in Australia. Over oceans sounds good, but often the surface winds can be stronger than its cruise speed. Is it amphibious?
There was a program in UUSR, years ago, for large jet freighters using over-wing engines and wings designed for ground-effect flying. The concept was fuel economy because of the ground effect. It was a flying boat, so coast to coast routes over water. Slowish speed and using ground effect met not so powerful or heavy engines.
I can't remember the max payload, but there were different sizes of craft. Whatever happened to it?

Super VC-10 20th Aug 2016 13:22

RAT 5 - do you mean the Ekranoplan?

A Squared 20th Aug 2016 13:26


Originally Posted by RAT 5 (Post 9480043)
I can't remember the max payload, but there were different sizes of craft. Whatever happened to it?

Turned out it was kind of a one trick pony which wasn't very useful.

RatherBeFlying 20th Aug 2016 13:35

How do you keep it on the ground after dropping a heavy load?
 
Serious tethering is required to avoid venting of expensive helium.

Then ballast must be sourced in said remote location.

Perhaps lay hose to body of water. Weight of hose will reduce payload, so can't go too far.

That or compress helium back into cylinders:confused:

Carbon Bootprint 20th Aug 2016 13:45


There was a program in UUSR, years ago, for large jet freighters using over-wing engines and wings designed for ground-effect flying. The concept was fuel economy because of the ground effect. It was a flying boat, so coast to coast routes over water. Slowish speed and using ground effect met not so powerful or heavy engines.
I can't remember the max payload, but there were different sizes of craft. Whatever happened to it?
It sounds like you're speaking of the Ekranoplan. Some are still around, most on a much smaller scale than that of the Caspian Sea Monster which may be the craft you are referring to.

It was basically built as a troop transport, though could have served other purposes. It wasn't that slow at all, as marine vessels go, and during its time of existence it posed a bit of a quandary for the IMO as to how to regulate a +400 km/h vehicle that was intended to co-exist with regular ship traffic.

As to what happened to it, it pretty much ran out of steam when the Soviet Union came down. It probably wasn't that practical or economical or efficient for most purposes (like the Airlander?). Nevertheless, a very fascinating venture (like the Airlander).

A Squared 20th Aug 2016 13:53


Originally Posted by JOE-FBS (Post 9479905)
It is also worth noting that those misty eyed romantics that run Lockheed Martin are also spending money on a similar programme to HAV.

Lockheed Martin is investigating more or less stationary surveillance/communications platforms. As I have already stated, I think that airships offer promise for this application. Plying air commerce ... not so much.



Originally Posted by JOE-FBS (Post 9479905)
While constantly comparing HAV to the airships of the 1930s makes about as much sense as comparing an A350 to a Ju52,

Well, no not really. The JU52 became obsolete because there were better versions of the same technology (fixed wing, heavier than air aircraft) , not because the fundamental technology lacked promise and application compared to other technologies. That's 2 completely different concepts. It's worth noting that if airplane technology had reached a plateau with the JU52, if some technological barrier had prevented refining airplane technology past that point, the JU52 would still be in service, because even in it's crude 1930's form, the airplane it would still offer powerful advantages over other forms of transport available today. The ability to travel well over twice practical sustained driving speed, and do it in a straight line without roads or rails, and over mountains, swamps and water, would still have application, because there's nothing that does what it does. By contrast, the airship fell out of use because other technologies developed which could do almost everything the airship could do, but better and faster.

Point being, there's a world of difference between "That stage of development of that particular technology is obsolete because later refinements of the same technology perform much better" and "That technology became obsolete because other technologies perform much better"


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