Translational lift flying backwards
I just can't for the life of me think why on earth you would want to do that.
How many times did he get it wrong before he got it right and turned it into a party trick?
How many times did he get it wrong before he got it right and turned it into a party trick?
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My IP demonstrated backwards auto entries in flight school lo those many years ago. The only safe landing area might not be in front of you, and you might not have enough altitude for a turning auto to it. We never touched down backwards, we transitioned to forward movement in time to touch down going forward. I'm not sure the TH-55 would do a successful backwards touchdown, but I suppose anything is possible.
Entering auto but bringing the speed right back - even to negative IAS - is a good technique with valid application as you say GP.
Trying to do an EOL to a piece of land you can't see however, is likely to cause more problems than it solves.
Trying to do an EOL to a piece of land you can't see however, is likely to cause more problems than it solves.
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Depends entirely on the land, or lack of it, and what is or isn't on it. Sometimes you have to take the lesser evil, because that's all the other evils are worse. In an ideal world, there is a runway dead ahead, in the right place for landing. But we don't live in ideal world.
We are in complete agreement Gomer Pylot - going backwards in auto so you can get visual with somewhere to touchdown is taught widely and is especially useful in a strong wind.
My question is about trying to to a 'flare, check, level cushion' EOL backwards which means you never see the LS - nothing but a party trick.
My question is about trying to to a 'flare, check, level cushion' EOL backwards which means you never see the LS - nothing but a party trick.
There is a person who is going to end up owning a crash site at some point in the future
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Look impressive - for a airshow display. My personal surviving instinct tells me - don't try this with a big birds. Me, personally, from the experience, am always taking in calculation - what else can go wrong.
Even in perfect conditions - with a nice, smooth infinite big landing spot right in front of me - would never play fool of myself and odds of fortune to do something like this.
But, again, what can I know? I am bus driver.
M
Even in perfect conditions - with a nice, smooth infinite big landing spot right in front of me - would never play fool of myself and odds of fortune to do something like this.
But, again, what can I know? I am bus driver.
M
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Me, personally, from the experience, am always taking in calculation - what else can go wrong.
- don't try this with a big birds.
Avoid imitations
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What amazing point is the video supposed to highlight?
And that wasn't.
Additional Data
Perhaps if he takes a look into this thread, Mons. Lappos could paste in a video of himself doing a very interesting bit of backward flying with a modified S-76B that he flew in conjunction with the 1995 Paris Airshow.
Fling-Wings flying their Arze reversing?????????
It's just toooo Hard 
(backwards flight) 
hmmmmmm what is the actual useful purpose for flying backwards???? 
(backward Auto from a good height to eventually get 65knots fwd ASI- OK) 
But....If there isn't a good reason for flying low level at high speeds with ETL+ in reverse, bar challenging one's (superior?) Skills 
then.....otherwise Airmanship dictates taking the Safest, or at least more Safer options, thus avoiding that area of flight; as it has additional risks, challenges & (potential) dangers 
OmOmOm
(backwards flight) hmmmmmm what is the actual useful purpose for flying backwards???? (backward Auto from a good height to eventually get 65knots fwd ASI- OK) But....If there isn't a good reason for flying low level at high speeds with ETL+ in reverse, bar challenging one's (superior?) Skills then.....otherwise Airmanship dictates taking the Safest, or at least more Safer options, thus avoiding that area of flight; as it has additional risks, challenges & (potential) dangers OmOmOm
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At some point I have a feeling that here is a splitted discussion between backward flight transition (than can be usefull in certain condition) and circus flying and opening beer bottles with helicopter...
Are the pilots flying in Red Bull race best FW pilots in the world? If so, than rearward AR is essential thing in every heli pilot training.
If not - than it is good to know that it is possible; essence of flying helicopter is to do your job safely and correct with high enough safe margin.
That is my opinion. Doesn't mean that I wouldn't be able to do something simillar in helicopter like this. But, at the end of the line, good pilot is living pilot.
Mike
Are the pilots flying in Red Bull race best FW pilots in the world? If so, than rearward AR is essential thing in every heli pilot training.
If not - than it is good to know that it is possible; essence of flying helicopter is to do your job safely and correct with high enough safe margin.
That is my opinion. Doesn't mean that I wouldn't be able to do something simillar in helicopter like this. But, at the end of the line, good pilot is living pilot.
Mike
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how can we forget Paris?
JohnDixson hinted at a story about the Paris air show that fits perfectly with this thread about flying backwards.
First, some aerodynamic background. The rotor does not know which way it's going, so that flying backwards is actually no different to the rotor than flying sideward, or forward. Where the rotor not attached to a fuselage you would feel perfectly comfortable at hundred knots backward. What does get you feeling funny on the controls is the effect the sideward or rearward flight has on the horizontal tail, the vertical tail and tail rotor. Basically, those tail feathers are like the feathers of a dart, and they try to force the aircraft to point its nose into the wind. Try throwing a dart backward, feathers first, and note how it flips forward. About halfway into its journey, it goes point first and sticks its nose into the wall. Your helicopter does the same thing, and you spend most of your effort in rearward flight fighting the horizontal and vertical tails. This makes your cyclic and pedals workload very high. Any missed timings on the controls, and the aircraft literally tries to swap ends. If it does so, it does so quickly and you are a passenger for a few seconds, usually an anxious passenger..
The most disturbing thing about rearward flight is how the horizontal tail tries to take over. Because the horizontal tail stabilizes your pitch axis in forward flight, it destabilizes the pitch axis in rearward flight. You can tell how strong this effect is when you recover from rearward flight and the nose pitches way down during the deceleration. While it's generally foolish to fly rearward at appreciable speed, doing a pedal turn in a brisk wind is the same thing.
Now on to Paris! It was 1993, and JohnDixson & I had brought our latest toys to the air show. He had the latest model UH 60L and I had the experimental demonstrator that we called the Fantail. A quick Google search of the Sikorsky fantail will show you a picture of the modified S 76B with the fan. It was the prototype for the Comanche, which proved the effectiveness of the yaw device.
We were at the Le Bourget heliport and flying back to Issi Les Moulineaux, diagonally across Paris. Flying with me in the fantail was Etienne Herrenschmidt, a fine test pilot – my counterpart at Eurocopter. We took off in formation with the Black Hawk, JohnDixson in the lead. I asked John to hold steady at 80knots, and then pressed full left pedal and popped the aircraft into rearward flight. As we trimmed in formation with the Black Hawk, he going forward, and we going backwards, Etienne whistled under his breath "Formidable!" We flew two thirds of the way around Paris backward!
I didn't feel brave enough to shoot a backward approach to the Issy heliport (not from a courage standpoint, more from a "Will he get thrown out of France?" standpoint) and so I swung the aircraft nose first on long final. Etienne was grinning ear to ear as we settled into a hover!
So much for backward flight transition!
how important is it to fly backward? For civil helicopters probably not very important, for military helicopters, it means you can point your weapons in seconds perhaps twice as fast as making a bank, so that large rearward flight speed envelopes might buy you the ability to finish your mission.
A vanilla video of the Fantail: Sikorsky H-76 Eagle FANTAIL Demonstrator - YouTube
some Comanche sideward flight, similar to that we proved on the H76 Fantail: RAH-66 COMANCHE - YouTube
First, some aerodynamic background. The rotor does not know which way it's going, so that flying backwards is actually no different to the rotor than flying sideward, or forward. Where the rotor not attached to a fuselage you would feel perfectly comfortable at hundred knots backward. What does get you feeling funny on the controls is the effect the sideward or rearward flight has on the horizontal tail, the vertical tail and tail rotor. Basically, those tail feathers are like the feathers of a dart, and they try to force the aircraft to point its nose into the wind. Try throwing a dart backward, feathers first, and note how it flips forward. About halfway into its journey, it goes point first and sticks its nose into the wall. Your helicopter does the same thing, and you spend most of your effort in rearward flight fighting the horizontal and vertical tails. This makes your cyclic and pedals workload very high. Any missed timings on the controls, and the aircraft literally tries to swap ends. If it does so, it does so quickly and you are a passenger for a few seconds, usually an anxious passenger..
The most disturbing thing about rearward flight is how the horizontal tail tries to take over. Because the horizontal tail stabilizes your pitch axis in forward flight, it destabilizes the pitch axis in rearward flight. You can tell how strong this effect is when you recover from rearward flight and the nose pitches way down during the deceleration. While it's generally foolish to fly rearward at appreciable speed, doing a pedal turn in a brisk wind is the same thing.
Now on to Paris! It was 1993, and JohnDixson & I had brought our latest toys to the air show. He had the latest model UH 60L and I had the experimental demonstrator that we called the Fantail. A quick Google search of the Sikorsky fantail will show you a picture of the modified S 76B with the fan. It was the prototype for the Comanche, which proved the effectiveness of the yaw device.
We were at the Le Bourget heliport and flying back to Issi Les Moulineaux, diagonally across Paris. Flying with me in the fantail was Etienne Herrenschmidt, a fine test pilot – my counterpart at Eurocopter. We took off in formation with the Black Hawk, JohnDixson in the lead. I asked John to hold steady at 80knots, and then pressed full left pedal and popped the aircraft into rearward flight. As we trimmed in formation with the Black Hawk, he going forward, and we going backwards, Etienne whistled under his breath "Formidable!" We flew two thirds of the way around Paris backward!
I didn't feel brave enough to shoot a backward approach to the Issy heliport (not from a courage standpoint, more from a "Will he get thrown out of France?" standpoint) and so I swung the aircraft nose first on long final. Etienne was grinning ear to ear as we settled into a hover!
So much for backward flight transition!
how important is it to fly backward? For civil helicopters probably not very important, for military helicopters, it means you can point your weapons in seconds perhaps twice as fast as making a bank, so that large rearward flight speed envelopes might buy you the ability to finish your mission.
A vanilla video of the Fantail: Sikorsky H-76 Eagle FANTAIL Demonstrator - YouTube
some Comanche sideward flight, similar to that we proved on the H76 Fantail: RAH-66 COMANCHE - YouTube
