Cathay hovers in midair

donvito99

...just wow

http://www.liveleak.com/view?i=d16_1320894540&p=1

sparrowcar

What about wind sheer, engine failure... Why wont someone think of the children. :eek:

Awesome video donvito99, thanks.

Nissan doctor

Brave would be one description.

Its looks amazing but what if the wind suddenly dropped or they had a tech problem or something? At that altitude they would never recover!

helimachoptor

Pretty impressive

shamrock421

https://www.youtube.com/watch?v=Qh2sWSVRrmo

Tenger

Nissan doctor wrote: »

Brave would be one description.

Its looks amazing but what if the wind suddenly dropped or they had a tech problem or something? At that altitude they would never recover!

Looks like it was at an airshow, I doubt this was a impulsive decision, these guys would know what they can and can't do with that aircraft, remember that the aircraft itself can over-ride pilot input to prevent the aircraft exceeding the flight envelope.

Nissan doctor

Tenger wrote: »

Looks like it was at an airshow, I doubt this was a impulsive decision, these guys would know what they can and can't do with that aircraft, remember that the aircraft itself can over-ride pilot input to prevent the aircraft exceeding the flight envelope.

True, but no amount of computer or pilot imput can control the wind.
IMO, at that altitude, if the wind dropped for even a few seconds you'd be looking at an a330 shaped scorch mark on the ground.

cuterob

yep that thing would drop like a (230) ton of bricks

Danbo!

Nissan doctor wrote: »

True, but no amount of computer or pilot imput can control the wind.
IMO, at that altitude, if the wind dropped for even a few seconds you'd be looking at an a330 shaped scorch mark on the ground.

The pilots putting too much faith in airbus' fly by wire tech.

Happened before when a French pilot tried to push the fly by wire and ****ed it up. Amazingly only 3 were killed.

Ignore the audio commentary, it's a poorly researched documentary.

https://www.youtube.com/watch?v=a5NXpar4Ouw

Real story here: http://en.m.wikipedia.org/wiki/Air_France_Flight_296

The book fly by wire has a great account about this too

mickdw

Madness. If wind dropped, that was slamming into the ground. I dont think this will be the last we hear of that.

Cessna_Pilot

Nissan doctor wrote: »

True, but no amount of computer or pilot imput can control the wind.
IMO, at that altitude, if the wind dropped for even a few seconds you'd be looking at an a330 shaped scorch mark on the ground.

I very much doubt there was a HASELL check done!

Anyway iirc this is from a Farnborough airshow, many years ago!

lord lucan

Cessna_Pilot wrote: »

Anyway iirc this is from a Farnborough airshow, many years ago!

1994 apparently. Airbus pilots flying,not CX.

amdublin

That's a freaky video :eek:

eatmyshorts

Danbo! wrote: »

The pilots putting too much faith in airbus' fly by wire tech.

Happened before when a French pilot tried to push the fly by wire and ****ed it up. Amazingly only 3 were killed. o

Nothing to do with misplaced "faith" or pushing the FBW. It was a simple lack of understanding of the A320 flight control laws. Alpha floor is not available below 100' RA. The aircraft performed exactly as it was designed to do.

Only those who have never flown an Airbus are overly critical of it. It boils down to simple ignorance.

shedweller

Reminds me of those piper cubs landing and taking off in their own length!

mickdw

eatmyshorts wrote: »

Nothing to do with misplaced "faith" or pushing the FBW. It was a simple lack of understanding of the A320 flight control laws. Alpha floor is not available below 100' RA. The aircraft performed exactly as it was designed to do.

Only those who have never flown an Airbus are overly critical of it. It boils down to simple ignorance.

So its not fully dependant on a strong headwind to make it stay in the air at that speed in that video?

eatmyshorts

mickdw wrote: »

So its not fully dependant on a strong headwind to make it stay in the air at that speed in that video?

My reply was in response to a post about the AF A320 crash in Basle.

The slow ground speed in the 330 video is dependent on the headwind. But remember that an aircraft doesn't care about ground speed. It's airspeed that is the critical factor. It could have done a fly past with a ground speed of 300 knots, but still be only "hanging" in the air with an airspeed of 120 knots if it had a tailwind.

vicwatson

Judging by the other videos surrounding it, is it not vide edited? I mean how the hell can an aircraft like this fight against gravity? I find it hard to believe, the equivalent of video photoshopping me thinks.

I'll stand corrected If anyone can show me other videos where a similar aircraft can suspend itself in mid-air:rolleyes:

If however I'm wrong, I say well done the pilots - awesome !, I also say why the heck haven't Airbus/Cathay Pacific got a professional video crew there to get this video viral !!

phonypony

vicwatson wrote: »

Judging by the other videos surrounding it, is it not vide edited? I mean how the hell can an aircraft like this fight against gravity? I find it hard to believe, the equivalent of video photoshopping me thinks.

I'll stand corrected If anyone can show me other videos where a similar aircraft can suspend itself in mid-air:rolleyes:

http://www.youtube.com/watch?v=0nqVG1zC7t0
It's possible to go backwards too. You're not fighting gravity, you're still flying through the air, but the wind is slowing your progress in relation to the ground. you have airspeed, just not groundspeed

vicwatson

It's possible to go backwards too. You're not fighting gravity, you're still flying through the air, but the wind is slowing your progress in relation to the ground. you have airspeed, just not groundspeed

So it doesn't actually stop dead per se? It obviously still has momentum, of some sort.

Your video link doesn't convince me, a cessna and an airbus are two seperate machines !

phonypony

vicwatson wrote: »

Your video link doesn't convince me, a cessna and an airbus are two seperate machines !

it's not how big it is, it's what you do with it!(or so i'm told...) as long as the relative wind is strong enough. In real world conditions you're probably not gonna see an A330 hover so close to the ground, the mean wind usually wouldn't be strong enough to safely hover, there's a bit of an illusion in the video in that respect. just like an ATR72 may appear to rotate and climb out at a faster groundspeed than a 747, simply because of its sheer size. But the hover is physically possible. Think of it this way: the aircraft is flying in a body of air, that body of air is moving across the ground in the opposite direction. The plane itself doesn't care about the ground.

vicwatson

It would want to be some body of air to hold up 230 tonnes of aircraft, that's all I'm sayin' y'know.

Tenger

vicwatson wrote: »

I also say why the heck haven't Airbus/Cathay Pacific got a professional video crew there to get this video viral !!

I believe this video was shot in the early/mid 90's at Farnborough, the A330 was being shown off. (And the mucky weather doesn't help)

And as dramatic as this looks it does not sell aircraft as no airline needs this 'ability'. So why would Airbus set up a video like this?
I would guess this was planned as a low speed pass over display but became a 'hover' due to the strong headwinds at that level?



To add to vicwatson's musings- think of crossing the Atlantic, this can take from 6-8 hours, all depending on windspeed against you. The route is the same and the distance is the same but due to the 'body of air' moving against you it takes 2 hours longer.

Nissan doctor

vicwatson wrote: »

It would want to be some body of air to hold up 230 tonnes of aircraft, that's all I'm sayin' y'know.

The weight of the aircraft isn't so much the factor. Its the speed of the air passing over the wings. This air speed can be created by the engines pushing the plane into the air or the air itself moving at the required speed(wind)

Imagine it this way, if a plane needs 200knots air speed to take off then if the plane was stationary on the ground and you were(somehow) able to blow air at the plane at 200knots, the plane could take off and 'fly' in mid air, without actually moving forward relative to the ground.

Its the same theory in practice on aircraft carriers, they always sail at full speed into the wind when aircraft are landing and taking off.

vicwatson

I believe this video was shot in the early/mid 90's at Farnborough, the A330 was being shown of

In Cathay Colours

And as dramatic as this looks it does not sell aircraft as no airline needs this 'ability'. So why would Airbus set up a video like this?
I would guess this was planned as a low speed pass over display but became a 'hover' due to the strong headwinds at that level?

I agree it does not have to sell aircraft, far from it. but it's a nice promotional video for Cathay. Don't you think :rolleyes:

To add to vicwatson's musings

Musings? really you think it's musings?

think of crossing the Atlantic, this can take from 6-8 hours, all depending on windspeed against you. The route is the same and the distance is the same but due to the 'body of air' moving against you it takes 2 hours longer.

Is this not known as predominant wind flow - E-W for example?

Its the speed of the air passing over the wings.

That's how aircraft fly right?

Prove to me how an airbus of 230 tonnes can "hang" and I'm in the zone.

Nissan doctor

vicwatson wrote: »

That's how aircraft fly right?

Prove to me how an airbus of 230 tonnes can "hang" and I'm in the zone.

I explained it as simply as I know how. I think your just not grasping the concept of airspeed entirely.

The speed that a plane is doing in relation to the ground(ground speed), technically, has nothing to do with its ability to fly.

Tenger

vicwatson wrote: »

That's how aircraft fly right?

Prove to me how an airbus of 230 tonnes can "hang" and I'm in the zone

If the air passing OVER the wings is of the correct velocity then it will generate enough lift (negative pressure) to keep the aircraft in the air.
This will happen regardless of what the actual groundspeed is.

It does seem to defy logic, but the science is proven.
Lift is generate by airflow over the wings, aircraft use forward velocity to achieve this, but with enough windspeed then the actual wing does not need to be moving very fast.

And I do not believe that A330 actually 'hovered', I'm sure we have all seen slow approaches into landing by aircraft where they almost seem to stop. I think this video is just a more extreme example of this phenomenon.

Nissan doctor

Wasn't there a video somewhere years ago of a c130 doing this and it actually started going backwards?

Tea_Bag

Nissan doctor wrote: »

Wasn't there a video somewhere years ago of a c130 doing this and it actually started going backwards?

I'd love to see that! great video OP.

wittymoniker

vicwatson wrote: »

In Cathay Colours


I agree it does not have to sell aircraft, far from it. but it's a nice promotional video for Cathay. Don't you think :rolleyes:


Musings? really you think it's musings?



Is this not known as predominant wind flow - E-W for example?



That's how aircraft fly right?

Prove to me how an airbus of 230 tonnes can "hang" and I'm in the zone.

If the wind speed and direction are appropriate, a stationary aircraft will get airborne. In the absence of these conditions the aircraft needs to propel its self through the air to create the airflow. The greater the airflow present before the propulsion is required the less forward movement (ground speed) is needed. It's a fundamental principal known as relative wind.

phonypony

wittymoniker wrote: »

If the wind speed and direction are appropriate, a stationary aircraft will get airborne.

As demonstrated here: http://www.liveleak.com/view?i=9f4_1321461076

tu2j2

vicwatson wrote: »

Prove to me how an airbus of 230 tonnes can "hang" and I'm in the zone.

Its simple enough really.

Take a cessna or something else small as an example, say it has a stall speed of 50kts, if you fly this plane into a 50kt headwind at 50kts indicated airspeed then relative to the ground you are traveling at 0kts, 60kt headwind and your traveling at -10kts relative to the ground but your indicated airspeed is still 50kts. The same applies to an Airbus just the numbers will be a but higher.

An aircraft flies based on the flow of air over its wings, its speed relative to the ground is irrelevant to its ability to stay airborne.

Su Campu

I seriously hope that the people questioning how a plane can hover above the ground are not pilots! It's the basics of aeronautics, the first thing pilots are taught - Airspeed. Groundspeed comes later, when they start planning their cross country navs.

In the original video, I would estimate that the A330 isn't actually "hovering" anyway, and is doing around 30-40 knots over the ground. Look at it again, and remember, it is a large plane, so that can fool one into thinking it's going slower that it actually is.

It's still a dodgy stunt to be doing though!