How did he do this?
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Any (heavier than air) aircraft can achieve 0G. How long it can be sustained and whether or not it is a good idea are different matters.
By pulling the nose up and then pushing it down.
How did he do this?
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Forgive me for thinking "what an idiot...."
What happens when one of the many things flying around loose in the plane falls to the floor unnoticed and then gets in the way of the rudder or brakes at a critical moment - very clever. Coke is also really good at ruining electronics if spilt on them
I dont know where in the world the clip with the dog was filmed, in many places that might be regarded as cruelty
"Hassell" comes to mind as well -HEIGHT AIRFRAME STRAPS SECURITY ENGINE LOOKOUT LOCATION
If you want to play, then take a ball on the beach, not risk your mates and pets just to look "clever"
What happens when one of the many things flying around loose in the plane falls to the floor unnoticed and then gets in the way of the rudder or brakes at a critical moment - very clever. Coke is also really good at ruining electronics if spilt on them
I dont know where in the world the clip with the dog was filmed, in many places that might be regarded as cruelty
"Hassell" comes to mind as well -HEIGHT AIRFRAME STRAPS SECURITY ENGINE LOOKOUT LOCATION
If you want to play, then take a ball on the beach, not risk your mates and pets just to look "clever"
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To a point, yes.. but only to a point. Mostly the loose objects.
The whole reason most of us go flying is to have fun, to 'play'. If pushing over at zero G is 'risky', god help us, especially those who fly aeros..
What are the load limits on a PA28, in the most restrictive category?
The whole reason most of us go flying is to have fun, to 'play'. If pushing over at zero G is 'risky', god help us, especially those who fly aeros..
What are the load limits on a PA28, in the most restrictive category?
Mistrust in Management
Zero G is just that - no loading on the wings whatsoever. One could argue that the structure was at that moment under less chance of failure than when parked. (when parked the wing top skin is effectively under a 'negative G' load due to the mass of fuel etc)
A few lads having a bit of fun - quite normal.
Regards
Exeng
A few lads having a bit of fun - quite normal.
Regards
Exeng
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I am surprised, fun can be fun - when it is planned... Having loose objects endangers everyone in the aircraft. The only fun in this case was someone being an idiot and placing thier friends at risk - WHY. Was it just to feed an ego?
If it had been a boy racer rather than a pilot would the attitude be the same? Would it still be classed as "fun"?
To me its the same as someone driving a car to the limits, its a risk which can be avoided.
Aero's are great fun and I agree about the comments about zero g loading. However aero's should be planned. Part of that planning should include making sure there are no loose objects, especially a can of coke in your mates hand.
And before someone asks, I have flown a lot of hours for fun doing aerobatics.... It was always planned and prepared for.
If it had been a boy racer rather than a pilot would the attitude be the same? Would it still be classed as "fun"?
To me its the same as someone driving a car to the limits, its a risk which can be avoided.
Aero's are great fun and I agree about the comments about zero g loading. However aero's should be planned. Part of that planning should include making sure there are no loose objects, especially a can of coke in your mates hand.
And before someone asks, I have flown a lot of hours for fun doing aerobatics.... It was always planned and prepared for.
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I agree. Aeros is quite fun but requires planning. No loose objects, passengers properly briefed and knowing the limitations of the plane.
The zero-g wing loading is not a problem. The wings will not come off under zero-g for reasons mentioned. But you may have other issues.
Even under the slightest negative g (which is required to get stuff off the floor - under zero g it would just remain in place) your carbs may overflow and fuel will find its way to the wrong side of the tank, unporting the fuel pickup and possibly causing fuel to exit via the vent lines. Short term effect is that the engine loses power immediately, slightly long term effect (10+ seconds) is that the fuel pressure drops and air might be finding its way into the fuel lines. All this will recover, eventually, when you resume normal flight, but do you have the patience and altitude to wait for that? Did you turn the fuel pump on before you started playing? Do you even have a fuel pump or is it a gravity fed system?
And what about the oil system? Under negative g the engine might be chucking its oil overboard through the engine breeder.
Futhermore, after a parabolic zero-g flight you need to recover. How much g are you pulling then? If you have backseat passengers the aircraft is probably limited to the N category - the U category requires that the back seats are empty in a lot of cases. What are the g limits of the aircraft in the N category?
Aeros, including zero-g flight is great fun but do it in an aerobatics aircraft (even a C152 Aerobat would do zero-g flights) and do it with proper preparation.
The zero-g wing loading is not a problem. The wings will not come off under zero-g for reasons mentioned. But you may have other issues.
Even under the slightest negative g (which is required to get stuff off the floor - under zero g it would just remain in place) your carbs may overflow and fuel will find its way to the wrong side of the tank, unporting the fuel pickup and possibly causing fuel to exit via the vent lines. Short term effect is that the engine loses power immediately, slightly long term effect (10+ seconds) is that the fuel pressure drops and air might be finding its way into the fuel lines. All this will recover, eventually, when you resume normal flight, but do you have the patience and altitude to wait for that? Did you turn the fuel pump on before you started playing? Do you even have a fuel pump or is it a gravity fed system?
And what about the oil system? Under negative g the engine might be chucking its oil overboard through the engine breeder.
Futhermore, after a parabolic zero-g flight you need to recover. How much g are you pulling then? If you have backseat passengers the aircraft is probably limited to the N category - the U category requires that the back seats are empty in a lot of cases. What are the g limits of the aircraft in the N category?
Aeros, including zero-g flight is great fun but do it in an aerobatics aircraft (even a C152 Aerobat would do zero-g flights) and do it with proper preparation.
The Cherokee in normal category is limited to +3.8.
The many times I've done this sort of thing (sans coke can- coke is a toxic concoction best used for cleaning coins) the recovery from such a brief zero g episode typically went to about 1.5, maybe 2 G. Typical airspeed between 90 and 120kt (vno) indicated.
Generally it was quite a bit tamer/smoother than an unusual attitudes session under the hood.
The many times I've done this sort of thing (sans coke can- coke is a toxic concoction best used for cleaning coins) the recovery from such a brief zero g episode typically went to about 1.5, maybe 2 G. Typical airspeed between 90 and 120kt (vno) indicated.
Generally it was quite a bit tamer/smoother than an unusual attitudes session under the hood.
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I do this every now and again, using a pencil held in front of me and released once 0 G has been achieved. I then see how long I can 'hover' the pencil for(normally a couple of seconds). Everything else is secured prior to the exercise.
It generally reuires no more than a 2.5 G pull to recover from a 30 degrees nose down condition.
There is nothing wrong with a bit of fun, provided it is executed safely.
As far as pushing 1/2 or one negative G in any aeroplane goes, if you think this will stop an engine or introduce a risk of fire due to fuel travelling out of vent tubes: Get Real! Do you really think any aeroplane would have a design fault as dangerous as that allowed?
It generally reuires no more than a 2.5 G pull to recover from a 30 degrees nose down condition.
There is nothing wrong with a bit of fun, provided it is executed safely.
As far as pushing 1/2 or one negative G in any aeroplane goes, if you think this will stop an engine or introduce a risk of fire due to fuel travelling out of vent tubes: Get Real! Do you really think any aeroplane would have a design fault as dangerous as that allowed?
Well, every time I've gone even a hint negative in a non-injected aircraft, the engine has obliged by immediately going fairly quiet. Normal power is restored immediately as soon as positive G is restored. (Throttle closed as soon as it dies, and smoothly opened again as required.
Even the aircraft I did an aero rating in (the mighty 152) was not supposed to be operated inverted. The oil pressure drops after a few seconds. At that point, positive loading should be restored PDQ. It's not terribly critical, as it's not producing power at the time. So my instructor informed me. But you don't dick around gliding inverted for, say, half a minute at a time.
Even the aircraft I did an aero rating in (the mighty 152) was not supposed to be operated inverted. The oil pressure drops after a few seconds. At that point, positive loading should be restored PDQ. It's not terribly critical, as it's not producing power at the time. So my instructor informed me. But you don't dick around gliding inverted for, say, half a minute at a time.
I have some vague recollection of reading a story in the crash comics of a european R44 fatal where there were dog caused scratchs all over the lower inside of the front window. Apparently the heli speared in from height so it wern't post accident. Recomendations were made to other pilots to secure pets in aircraft.
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Moderator
Oh the horror! Zero G, and floating her teddy bear around the cockpit was an indispensibe trick to keeing my then 5 year old from getting bored during a flight home.
I am aware of many dumber things being done in planes than letting a Coke can loose during zero G flight.
I did the -1 G flight testing of the DA-42-360, as it was a certification requirement for the engine STC. The engines did cough a bit, but sprang back to life immediately upon restoration of G. We did throw out some engine oil each time, and the observers on the ground reported seening the cloud of oil mist. But, that was -1 G, when anything loose is pinned to the ceiling.
Zero G is a non-event as long as it is planned, the area of flight is appropriate, the cabin is secure, and occupants willing.
I'm sure there have been many more articles fouled in the nether regions of a cockpit from simple poor housekeeping while flying, than from planned zero G flight!
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And what about the oil system? Under negative g the engine might be chucking its oil overboard through the engine breeder.
So if you are able to breed engines where's the problem with losing one occasionally?
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I've had it happen over the moutains occasionally. It's a bu66er when your Pooleys ends up in the back seat.
I believe the cam lobes are the highest loaded part of the engine. They have the same load power on or power off!
D.O.
I believe the cam lobes are the highest loaded part of the engine. They have the same load power on or power off!
D.O.