Pilatus PC6 Diving
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Pilatus PC6 Diving
Hi everybody,
I've just started to fly with a Pilatus Porter B2-H4, for skydivers activity, and i saw some video on the web, where some PC6 dive to follow skydivers after they jump.
Now I'm at the beginning of this experience so i'm still trying to understand all the limit of the airplane, and what can really be done with it.
But I'm really courius to understand how to dive like that. From all the video it seems that the porter dive at an angle near 90° (but maybe is only an illusion of the images), in beta range for sure. What i can not understand is if they let the velocity arriving near the VNE, or in reality they dive a lot only at the beginning when the speed is still low, and then they push back a bit the stick.
Because i know that dive at speed higher than 110-120 Kts is not very safe and good for the plane.
Any one of you guys have tried this, or know something?
Thaks =)
Here an example of what i was talking
I've just started to fly with a Pilatus Porter B2-H4, for skydivers activity, and i saw some video on the web, where some PC6 dive to follow skydivers after they jump.
Now I'm at the beginning of this experience so i'm still trying to understand all the limit of the airplane, and what can really be done with it.
But I'm really courius to understand how to dive like that. From all the video it seems that the porter dive at an angle near 90° (but maybe is only an illusion of the images), in beta range for sure. What i can not understand is if they let the velocity arriving near the VNE, or in reality they dive a lot only at the beginning when the speed is still low, and then they push back a bit the stick.
Because i know that dive at speed higher than 110-120 Kts is not very safe and good for the plane.
Any one of you guys have tried this, or know something?
Thaks =)
Here an example of what i was talking
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Just exactly what's wrong with diving at 120 kts? It's Vne has to be in the order of 150 kts or so and the Va has to close to 120kts. I would have thought the real limit would be the amount of reverse (if any) you can pull in the air so that the drag is great enough to limit the speed or the sustained maximum pitch angle (for oil and fuel). However, the AOM has to be final authority on this manoeuvre.
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Yes the VA is 119 Kts, and when you dive you are not in revers but in the beta Range. The manual suggest to go down at not more than 110 Kts in when you are in BETA range, but not for propeller problem, just to stress less the wings and fusolage.
The real problem is that if you dive very fast from a normal orizontal flight conditions (like the videos), the propeller can fail to enter the BETA and in this case the speed wil rise very fast, and an overtorque can also occour.
Also the aircraft is certified for utility category, but about 40 years ago. If you look at the wings and the control surfaces, they are like an ultralight airplane. Infact in the story of this plane there where some catastrofic crash, and serious damages due to excessive stress, but also to the fragility of the plane.
So to do this things you have to know very well what you are doing. This is why i was wondering if there was any Porter pilot around here that can give me some advise about this manouver.
The real problem is that if you dive very fast from a normal orizontal flight conditions (like the videos), the propeller can fail to enter the BETA and in this case the speed wil rise very fast, and an overtorque can also occour.
Also the aircraft is certified for utility category, but about 40 years ago. If you look at the wings and the control surfaces, they are like an ultralight airplane. Infact in the story of this plane there where some catastrofic crash, and serious damages due to excessive stress, but also to the fragility of the plane.
So to do this things you have to know very well what you are doing. This is why i was wondering if there was any Porter pilot around here that can give me some advise about this manouver.
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PC-6 speeds
Design diving speed (vd) 167 knots
never exceed speed (vne) 151 knots
design cruising speed (vc) 119 knots
max. Flap extended speed (vfe) 95 knots
stall speed (idle power) with flaps up (vs) 58 knots
stall speed (idle power) with flaps down (vso) 52 knots
max. Speed in level flight with max. Continuous power (vh) 125 knots
never exceed speed (vne) 151 knots
design cruising speed (vc) 119 knots
max. Flap extended speed (vfe) 95 knots
stall speed (idle power) with flaps up (vs) 58 knots
stall speed (idle power) with flaps down (vso) 52 knots
max. Speed in level flight with max. Continuous power (vh) 125 knots
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It is no big deal.
Para-dropping procedure is that the meatbombs have a preferred exit speed between 60-70 knots. As the last man leaves the power lever is retarded to the beta range about 65% reverse torque.
Coincidentally, the back pressure on the stick is released and the aircraft rolled. The nose falls by about the same amount as the roll so after 90 degrees of roll you have 90 degrees of nose down pitch and then getnle bacl pressure to prevent a further increase in speed.
I seem to remember either a high speed dive up to Vne or a spiral at Va depending on where you needed to land.
If the speed is above about 100 then the propeller will not enter the beta pitch range.
The Turbo-Beaver was also capable of this but you needed to pull to the buffet to get enough drag to stay with the jumpers.
Para-dropping procedure is that the meatbombs have a preferred exit speed between 60-70 knots. As the last man leaves the power lever is retarded to the beta range about 65% reverse torque.
Coincidentally, the back pressure on the stick is released and the aircraft rolled. The nose falls by about the same amount as the roll so after 90 degrees of roll you have 90 degrees of nose down pitch and then getnle bacl pressure to prevent a further increase in speed.
I seem to remember either a high speed dive up to Vne or a spiral at Va depending on where you needed to land.
If the speed is above about 100 then the propeller will not enter the beta pitch range.
The Turbo-Beaver was also capable of this but you needed to pull to the buffet to get enough drag to stay with the jumpers.
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You also get a lot of idiots trying to show off so do not believe that everything you see on the internet is within the aircraft limits.
These for example will be going past VNE. No other way to do it.
Bear in mind that a LOT of porters used for skydiving have accidents not all serious but many are.
Pilatus Porter crash at Moorsele in Belgium - Dropzone.com
http://www.liveleak.com/view?i=424_1212414796
Porter crash at Italian DZ in Ravenna
The one where the wing fell off may have been due to repeated journeys beyond VNE and then yanking back on the stick. Eventually a wing will fall off. You don't know what has gone on in the plane prior to you getting into it and it may just be some turbulence that takes it beyond its life. These are usually old, high time, hard worked aircraft. Be gentle to them and don't worry about looking cool.
Yeah have fun but don't do what those in the videos above are doing not only can you hit someone but if you end up overtaking a skydiver quickly, chances are you will go past VNE before the speed starts coming back.
Do you really need people posting videos on the net of what an awesome pilot you are
If that is important to you then it may be a video like the last one.
These for example will be going past VNE. No other way to do it.
Bear in mind that a LOT of porters used for skydiving have accidents not all serious but many are.
Pilatus Porter crash at Moorsele in Belgium - Dropzone.com
http://www.liveleak.com/view?i=424_1212414796
Porter crash at Italian DZ in Ravenna
The one where the wing fell off may have been due to repeated journeys beyond VNE and then yanking back on the stick. Eventually a wing will fall off. You don't know what has gone on in the plane prior to you getting into it and it may just be some turbulence that takes it beyond its life. These are usually old, high time, hard worked aircraft. Be gentle to them and don't worry about looking cool.
Yeah have fun but don't do what those in the videos above are doing not only can you hit someone but if you end up overtaking a skydiver quickly, chances are you will go past VNE before the speed starts coming back.
Do you really need people posting videos on the net of what an awesome pilot you are
If that is important to you then it may be a video like the last one.
