the sting or the ball?
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the sting or the ball?
what do other ppruners try to keep centred the ball or the string?
- if you keep the ball centred, this just means the cabins level. the better option probably; the spine is strait and it feels right although you could be crabing along even if the weight balance is out just a bit. there might also be a crosswind in the cabin (with the doors off). fuel consumtion is probably greater aswell.
- if you keep the string centred, this means the airflow over the aircraft is true but the cabin can be tilted to one side making it uncomfortable. better fuel consumptioon though.
keeping in mind only if the c.o.g. is in the exact right spot will the two be the same. (would be some pretty fiddley loading)
maybe half way between??
- if you keep the ball centred, this just means the cabins level. the better option probably; the spine is strait and it feels right although you could be crabing along even if the weight balance is out just a bit. there might also be a crosswind in the cabin (with the doors off). fuel consumtion is probably greater aswell.
- if you keep the string centred, this means the airflow over the aircraft is true but the cabin can be tilted to one side making it uncomfortable. better fuel consumptioon though.
keeping in mind only if the c.o.g. is in the exact right spot will the two be the same. (would be some pretty fiddley loading)
maybe half way between??
I center both on a transient basis....by going from stop to stop....I even out all the wear and tear on the airframe, tail rotor, and my backside.....find it a good way to exercise. A collateral benefit is the passengers do not get bored having the same perspective on the view out the windows. Equals the time each has a good view.
Gentleman Aviator
On RAF/CFS Gazelles, we used to teach string for day/vmc, ball for night or imc. There was quite a difference, and I always found "ball centred" less comfortable somehow. Of course, if you forgot to unhook the string on the walkround.............
Vorticey, I seem to remember we covered this on a previous thread - you are talking about inherent sideslip which is a neccessary consequence of producing anti torque force with tail rotor/tail fin. If you are lucky enough to have both a ball and string then you can choose whichever feels best - the only time the string is inaccurate is in a high power climb when the swirl of the downwash affects it.
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I learned to use the string on a Gazelle many moons ago aswell and still swear by it on the AS350 series today.
I fly Bells aswell which only have a ball and trying to centre the 2 balls on a 205 is a joke 'cos they tend to be cross-eyed most of the time no matter what you do.
The string is the most reliable piece of equipment on the whole machine.
I fly Bells aswell which only have a ball and trying to centre the 2 balls on a 205 is a joke 'cos they tend to be cross-eyed most of the time no matter what you do.
The string is the most reliable piece of equipment on the whole machine.
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I read somewhere, that you should note where the ball is while in the hover (slighthly left, centered, slightly right) and then fly to maintain that position. I'll vote for the string anyday however, it has the huge advantage that you're looking outside. Don't remember the last time I looked at the balance ball. Ah, now I do, it was when the string got all wound up! 
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On the RAF version of the Gazelle we discovered that the non-symmetrical instrument panel hung lower on the right side due to the extra weight pulling down on the "Barry mounts" (rubber anti-vibration mountings).
The judicious use of an en-route supplement stuffed under the panel brought it level and made the ball centre = string centre.
The judicious use of an en-route supplement stuffed under the panel brought it level and made the ball centre = string centre.
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Just to add my two cents worth.
We recently flew our venerable UH-1N (ex Canadian Air Force) with an offset lateral CG, for a stability and control exercise. With the ball centered, in cruise, we had about 10-12 degrees of sideslip, and when we flew with the ball in the same position it was in when hovering into wind, (about half a ball to the left), we had nearly zero sideslip.
Keeping the ball where it is in the hover gets my vote every time for ease of flying.
The string also works well in a high power climb with any airspeed above about 30 KIAS, and gives much better performance than using the ball.
For flight testing for performance, we use the slip string anytime we're below 60 KIAS, just for consistency.
Does anyone have an STC for a slip string on the Bell machines?
We recently flew our venerable UH-1N (ex Canadian Air Force) with an offset lateral CG, for a stability and control exercise. With the ball centered, in cruise, we had about 10-12 degrees of sideslip, and when we flew with the ball in the same position it was in when hovering into wind, (about half a ball to the left), we had nearly zero sideslip.
Keeping the ball where it is in the hover gets my vote every time for ease of flying.
The string also works well in a high power climb with any airspeed above about 30 KIAS, and gives much better performance than using the ball.
For flight testing for performance, we use the slip string anytime we're below 60 KIAS, just for consistency.
Does anyone have an STC for a slip string on the Bell machines?
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crab
you said- you are talking about inherent sideslip which is a neccessary consequence of producing anti torque force with tail rotor/tail fin.............ah- WRONG!
the inherant side slipe is stopped with disc offset in the hover and in flight. as for the roll on the cabin it can be basicaly eliminated with weight placement. you mus'nt have listend when i explained it before?
everyone seems to like the string better, thats what i was after.
the inherant side slipe is stopped with disc offset in the hover and in flight. as for the roll on the cabin it can be basicaly eliminated with weight placement. you mus'nt have listend when i explained it before?
everyone seems to like the string better, thats what i was after.
