Negative G manuever

Kalikiano

New Member
Not sure if this is the correct section for this:


Im interested in trying a negative G manuever but I don't know anything about it besides the google videos ive watched that look pretty fun. Im guessing its as simple as pitching up and then pitching down pretty quickly. I dont have my notes on me but I think a 172 can handle -1.5 G force even though I have no idea how much G this manuever would put on the plane.
 
I don't have my notes on me but I think a 172 can handle -1.5 G force even though I have no idea how much G this manuever would put on the plane.

You probably only need 0 g to do what you want, make objects float. -1 g would feel like you were hanging upside down in your seatbelt.
 
Before attempting any zero or negative-g maneuver, consider whether gravity is an integral element of your aircraft's fuel and/or oil systems necessary to keep that spinny thing up front spinning.
 
Not knowing your experience level, I would suggest going up with a CFI before attempting something outside your normal flying envelope...
 
Aloft hit the important part in his post -- if light or negative G will adversely affect the fuel or oil systems of your aircraft.

Having done this before a couple of times, you will probably lose power at the top of the bunt in most GA aircraft.
 
in the skyhawk XP "fuel pump on"

The non fuel pump skychickens will usually stall out the engine if you do anything zero g or lower. It is a non event and the engine restarts itself after you have regained positive G but it will get your attention.

I am not sure I would try this alone though having never been demo'd it before. And DEFINATELY NOT WITH A PASSENGER. It is a simply maneuver and usually you just fly an arc (is parabolic arc the word I am looking for here?)

Needless to say you simply "load the airplane" by gaining a little speed and then pitching up to maybe 20 degrees or whatever youd like and then at the top of the arc when airspeed is reducing you start a gradual but increasing push forward on the yoke to start the downside of the arc. Before you go make sure that the airplane is EMPTY of everything but yourself and there is nothing loose around. Keep your seatbelt nice and tight and start by maybe just putting your chart on your lap and watch that float a bit before you float.

Why this is a bad idea.

1- skychickens do not have instrumentation to tell you what G load you are putting on the airplane
2- unless you have done MANY hours of aerobatics you will not instinctively know what "G" you are at or imposing on the airplane.
3- unless you own the airplane you do not know where it has been, how do you know in the life of the airplane it hasnt been looped or barrelrolled and the +4 -2 Gs you are going to put on it will be the straw that broke the camels back and tear the wings off. You may think im crazy but I would guarantee that any cessna trainer over 20 years old has been looped and barrelrolled at least once. Crazy, I know.
4-Are you well versed in spin recovery? Do you know what will happen if you spin the airplane at a negative G load? Things to consider.


Me personally I would just find an aerobatics instructor and go up for an hour and have some real fun. When I was teaching acro I would have my private students want to go up for just a fun ride and the hour was theirs to see and demo whatever they wanted and go to down knowing that I was there to help them out if need be. I had hundreds of hours in the plane and as many hours teaching upset recovery and knew what the plane would do if they put in the incorrect inputs and how to fix it.

Not trying to scare you but there should be alot of thought process going into even such a mundane maneuver.
 
Before you go make sure that the airplane is EMPTY of everything but yourself and there is nothing loose around.

When I was instructing still I trained an VT ANG F16 guy (call sign "Cargo" if any of ya'll military guys know him... apparently he had a history of sorts) and he told me about the "lost pencil check". Apparently, despite all the useful velcro and and pockets on flight suits it is still possible to misplace your pencil. So, the prescribed method of finding it was roll the plane inverted and shake the stick back and forth. Pretty much anything that was on the floor would end up against the canopy so it was a simple matter of grabbing the pencil from above your head and then rolling the plane back over.
 
So, the prescribed method of finding it was roll the plane inverted and shake the stick back and forth. Pretty much anything that was on the floor would end up against the canopy so it was a simple matter of grabbing the pencil from above your head and then rolling the plane back over.


If only that would work in Cherokee then I'd never have to buy another pencil
 
Before attempting any zero or negative-g maneuver, consider whether gravity is an integral element of your aircraft's fuel and/or oil systems necessary to keep that spinny thing up front spinning.

You could go up really high then shut the motor off before you did it so that the engine didn't run without oil (if you puled the oil away from the mouth on the sump). Plus, its kinda cool to see how the airplane actually flies with the engine off, then re start the motor when you're getting to arround 3000 or so, its also kinda cool to see how the airplane actually glides.
 
Ahhhh, reminds me of the time my aerobatics instructor lost his pen. I was practicing barrel rolls and kind of fell out of a couple of them, then tried to compensate by shoving the nose up while inverted. He had the pen clipped onto his pocket but I guess my ham-fisted attempts at rolls were too much for the little clip. After roll #1: "Ooops, I lost my pen.....must be on the floor somewhere." A few mins later, after I botched a roll pretty badly and pulled over -1.5 g's: "Well, at least I found my pen." :)
 
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