Robinson R22 Corner [Archive copy]
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They put it there for a reason, and we are allowed to think for ourself, even though it's not SOP ( Yeah, I know, but hey.......it could save your as* one day !!! ).
Ofcourse any leaning will be performed on the ground ( if I recall correctly, their lawyers don't recommend inflight mixture manipulation ). !!
Ofcourse any leaning will be performed on the ground ( if I recall correctly, their lawyers don't recommend inflight mixture manipulation ). !!
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Dropping a Robinson
Information wanted please. I am trying to to do some evaluation on skid setups, and would be interested on any information from anyone who has had engine failure or other problems which have necessitated dropping a Robinson from eight feet or less, from a hover. I refer to structural damage rather than the cause. Many thanks, Bug.
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I'm assuming that you live somewhere that makes it inconvenient to attend the factory school - a pity, as it's a great school. Anyway, in the school they show you video tapes of their products being dropped (not hover auto - cut-the-string dropped) while they measure the skid distension.
I'd suggest you call RHC and ask to talk to Ken Martin or Pat Cox and see if they can get you some numbers.
I'd suggest you call RHC and ask to talk to Ken Martin or Pat Cox and see if they can get you some numbers.
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As part of the certification testing of the R22, they did some drop tests. RHC have a video which, as has been mentioned, is shown on their course. Its quite impressive to see how much the skids deflect, and then return.
From experience doing instruction, the R22 skids are pretty good at resisting damage from "drops": much more so than many other apparently stronger helicopters. However, helicopters can be dropped in various ways. Sometimes, even when the drop is not large, it can be awkward. If the drop is not just straight down, but has a lateral element, you can get damage. Not necessarily the skids, but damage to the MR gearbox and/or its fairing.
From experience doing instruction, the R22 skids are pretty good at resisting damage from "drops": much more so than many other apparently stronger helicopters. However, helicopters can be dropped in various ways. Sometimes, even when the drop is not large, it can be awkward. If the drop is not just straight down, but has a lateral element, you can get damage. Not necessarily the skids, but damage to the MR gearbox and/or its fairing.
Senis Semper Fidelis
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If a Robbo is dropped or put down hard and nearly level at impact , this can be seen after the event in the cross member at the rear of the cabin will show varying stages of deformity IE it wont be straight the bigger the bend the harder the hit, after that it in the other things like the tail boom drooping and the rotor mast moving(deflecting) so much that it will deform the roof around where it pokes out from the main body!
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Dropping an R22 may increase the bend in the beam that VFR mentions - however it is bent to some extent as it comes out the factory, so don't reject an R22 just because it is bent.
If I remember right, RHC specify a check of the height of the tail stinger above level ground as part of the check after a heavy landing - it will all be in the maintenance manual. Presumably it effectively checks that any deformation of the skids was elastic and that the skids system remains within limits.
I guess what I was trying to say earlier is that, in my experience you are more likely to get damage from drops, in practice, away from the skids.
If I remember right, RHC specify a check of the height of the tail stinger above level ground as part of the check after a heavy landing - it will all be in the maintenance manual. Presumably it effectively checks that any deformation of the skids was elastic and that the skids system remains within limits.
I guess what I was trying to say earlier is that, in my experience you are more likely to get damage from drops, in practice, away from the skids.
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R22 overspeed query
Hi - can anyone tell me why some sort of engine rpm limiter could not be incorporated into the design of an R22/R44?
It seems that a lot of low time pilots waste a fair amount of cash coughing up for accidental engine overspeeds and R22s remain grounded pending inspections when e.g. starting up with the throttle open or raising the collective without the governor on and not reacting quickly enough to reduce rpm.
Thanks
It seems that a lot of low time pilots waste a fair amount of cash coughing up for accidental engine overspeeds and R22s remain grounded pending inspections when e.g. starting up with the throttle open or raising the collective without the governor on and not reacting quickly enough to reduce rpm.
Thanks
Iconoclast
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I don't need no stinking limits.
To: rba194
Some automotive engines have over speed limiters, which either cut off the fuel supply or cut the ignition. On an automotive engine when you stop ignition or fuel the rear/front wheels through the transmission are still back driving the engine.
On the Robbie or any other helicopter the internal combustion engine is isolated by the free wheeling unit and when any overspend device were actuated the engine would most likely stop.
To put some type of limiter on an existing engine it would require re certification or that an STC be issued which would require much less paperwork than a full re certification.
Many years ago the US Army took delivery of a brand new H-34. A new pilot was transitioning from H-13s to the H-34. He started the engine while twisting or untwisting the throttle trying to get fuel pumped into the engine. The throttle canceller switch was misrigged and the engine caught with the throttle wide open. The engine went to 2800 RPM and there was so much force in the hydromechanical clutch that it broke and the engine was connected to the driveline. It took only one second under those conditions to make that brand new H-34 a write-off and it was taken to the training school as a training aid.
Some automotive engines have over speed limiters, which either cut off the fuel supply or cut the ignition. On an automotive engine when you stop ignition or fuel the rear/front wheels through the transmission are still back driving the engine.
On the Robbie or any other helicopter the internal combustion engine is isolated by the free wheeling unit and when any overspend device were actuated the engine would most likely stop.
To put some type of limiter on an existing engine it would require re certification or that an STC be issued which would require much less paperwork than a full re certification.
Many years ago the US Army took delivery of a brand new H-34. A new pilot was transitioning from H-13s to the H-34. He started the engine while twisting or untwisting the throttle trying to get fuel pumped into the engine. The throttle canceller switch was misrigged and the engine caught with the throttle wide open. The engine went to 2800 RPM and there was so much force in the hydromechanical clutch that it broke and the engine was connected to the driveline. It took only one second under those conditions to make that brand new H-34 a write-off and it was taken to the training school as a training aid.
rba:
Point taken - I've been there
To my mind, if the pilot follows the checklist, they're safe, and it's incumbent on the school to teach well enough to avoid it - not only in the "this is what you do and don't do" but "this is the time you concentrate on one task" sort of stuff.
Adding technology probably means the aircraft will be grounded with a limiter fault more often anyway.
Point taken - I've been there
To my mind, if the pilot follows the checklist, they're safe, and it's incumbent on the school to teach well enough to avoid it - not only in the "this is what you do and don't do" but "this is the time you concentrate on one task" sort of stuff.
Adding technology probably means the aircraft will be grounded with a limiter fault more often anyway.
The Original Whirly
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Most schools charge the insurance deductable/excess, frequently £1000. 
The most likely time for an overspeed at this time of year is the first flight of the day, when checking the carb heat, now that it's done at 100% RPM again rather than 75%. Carb ice melts, and RRPM goes up...and up...and up. It can do it very quickly sometimes, and you have to be quick to catch it,. I'm surprised there aren't more overspeeds in that situation.
The most likely time for an overspeed at this time of year is the first flight of the day, when checking the carb heat, now that it's done at 100% RPM again rather than 75%. Carb ice melts, and RRPM goes up...and up...and up. It can do it very quickly sometimes, and you have to be quick to catch it,. I'm surprised there aren't more overspeeds in that situation.
The R22 has reached the limit of it growth margins, adding any further weight to the aircraft would required a substantial redesign. Therefore, since virtually all developments will add weight to the aircraft they are ruled out as a matter of policy.
Anyway, adding an overspeed protection device is a small priority compared to the other things that big-R would change if it was worth doing....but of course it is not if you have a complete monopoly on the market (91%) last time I checked. The only customer migration big R has to worry about is customers moving from R22 to R44, hardly a big problem is it, having to take twice as much money off them...
I shouldn't expect too much more to happen to the R22 until R's had is forced...and even then it many not be worth his while, R44 accounts for over 80% of aircraft sales revenue and is in slightly less risky market [i.e. not a primary trainer].
Hope this helps
CRAN
Anyway, adding an overspeed protection device is a small priority compared to the other things that big-R would change if it was worth doing....but of course it is not if you have a complete monopoly on the market (91%) last time I checked. The only customer migration big R has to worry about is customers moving from R22 to R44, hardly a big problem is it, having to take twice as much money off them...
I shouldn't expect too much more to happen to the R22 until R's had is forced...and even then it many not be worth his while, R44 accounts for over 80% of aircraft sales revenue and is in slightly less risky market [i.e. not a primary trainer].
Hope this helps
CRAN
Cool as a moosp
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Whirly and anyone else, I have not yet received the POH ammendment to carry out the carb heat check on the R22 at "100%". Can you give me the date of the new page and I can chase it up? We usually get seamail updates to HKG...
The Original Whirly
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Dohhhhhhh!!! Here I am spreading rumours again. Oh well, this is a rumours forum. I haven't seen anything in writing either, as it happens. I got told we were back to doing it at 100%, and I just believed it. After nearly getting an overspeed, maybe I'll go back to 75% if no-one else knows of any change. Sorry for the confusion.
Senis Semper Fidelis
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Overspeeds on the R22 can and do occurr when in flight also, a very well known FTO rented to me on SFH basis one of their R22's what they omitted to tell me was that it had suffered from an overspeed by one student pilot whilst with one Fi and it reached in excess of 115%, I was the lucky guy who next flew this by now heap of scrap, one problem with any helicopter is the walk round pre flight, you can look and touch and rock about and twist things around, do all you full and free and then you Ts&Ps on start up, what you cant see are the stretched and completly goosed rotor bearings that are in the teetering head, and as far as I know there really is no way these can be checked from the pre-flight.
But dear reader, once airborne and reaching the types of velocity to start flying this problem will show its self, I am only here today I think because I weigh 90Kgs and have previously wrastled big things on farms, the stick shake that was induced from about 38knts was so severe I couldnt raise my thumb to press the radio button to declare a problem, I was forced to carry on and kept to a minimum of 500ft whislt working out what I had to do, the tide was in I couldnt land on the beach so I had to fly a long gently looping arc to get back to the field, after locking off the collective and using that free hand to comm with the tower, I then concentrated on getting that giant vibrator back to the ground, whilst doing my best to fly over green field and to miss the housing and factories that abound around EGNH, the fact that I am here tells you I got down, with the help of the tower by keeping everyone well away from me until I had got back down to hover taxi speed, when at that point the giant vibrator stopped.
After I had landed and done my run down and after flight checks I still couldnt see anything wrong with the rotor, or head despite now knowing something had happened to it and was sadly wrong, but as I was very slowly walking in I was met by certain people who proffessed they had forgotten to red card the Heli.
What I wonder would have been said if I had gone in!! needless to say that crowd of cowboys has never since had any money from me.
But I still dont know how you would see overspeed damage on any preflight
Vfr
But dear reader, once airborne and reaching the types of velocity to start flying this problem will show its self, I am only here today I think because I weigh 90Kgs and have previously wrastled big things on farms, the stick shake that was induced from about 38knts was so severe I couldnt raise my thumb to press the radio button to declare a problem, I was forced to carry on and kept to a minimum of 500ft whislt working out what I had to do, the tide was in I couldnt land on the beach so I had to fly a long gently looping arc to get back to the field, after locking off the collective and using that free hand to comm with the tower, I then concentrated on getting that giant vibrator back to the ground, whilst doing my best to fly over green field and to miss the housing and factories that abound around EGNH, the fact that I am here tells you I got down, with the help of the tower by keeping everyone well away from me until I had got back down to hover taxi speed, when at that point the giant vibrator stopped.
After I had landed and done my run down and after flight checks I still couldnt see anything wrong with the rotor, or head despite now knowing something had happened to it and was sadly wrong, but as I was very slowly walking in I was met by certain people who proffessed they had forgotten to red card the Heli.
What I wonder would have been said if I had gone in!! needless to say that crowd of cowboys has never since had any money from me.
But I still dont know how you would see overspeed damage on any preflight
Vfr
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Overspeeds
Vfr,
Dont know if this is going to be of any help to you because you may already be awear of this, but one way of checking for an over-speed on either the R22 or the R44 is to have a look at the nut that holds the cooling fan in place. There should be a line of white 'torque seal' drawn from on one side of the fan, across the nut and back onto the other side on the fan. If this line on the nut doesnt match up with the two lines on the fan then this may be an indication of an overspeed, allbeit an engine overspeed.
As to checking for brindled bearings in the blades, I dont think there is any way of checking them in a pre-flight, only when the blades come off the A/C.
PA321
Dont know if this is going to be of any help to you because you may already be awear of this, but one way of checking for an over-speed on either the R22 or the R44 is to have a look at the nut that holds the cooling fan in place. There should be a line of white 'torque seal' drawn from on one side of the fan, across the nut and back onto the other side on the fan. If this line on the nut doesnt match up with the two lines on the fan then this may be an indication of an overspeed, allbeit an engine overspeed.
As to checking for brindled bearings in the blades, I dont think there is any way of checking them in a pre-flight, only when the blades come off the A/C.
PA321
I has been taught to do always the carburetor heater check with my left hand in the throttle and the right in the "lever?" (stick between legs) , ALWAYS looking at the engine rpm , I can't see the problem with the ice and high rpm, you can always roll the throttle, but it's also true that I haven't flown in icing conditions... 
I think that there is no need for a rpm limiter , but I'm just a low time student
I think extacly the same...
A friend of mine , in the first hours almost had a overspeed but , as it should be he was with an instructor.
Regards.
I think that there is no need for a rpm limiter , but I'm just a low time student
To my mind, if the pilot follows the checklist, they're safe, and it's incumbent on the school to teach well enough to avoid it - not only in the "this is what you do and don't do" but "this is the time you concentrate on one task" sort of stuff.
A friend of mine , in the first hours almost had a overspeed but , as it should be he was with an instructor.
Regards.
Senis Semper Fidelis
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PA321,
Yes, on my preflight the white line was Ok and not cracked. have been told since that the only way a Rotor Overspeed can become known about is by those responsible being HONEST, sadly sometime Honesty is a very rare commodity.
Yes, on my preflight the white line was Ok and not cracked. have been told since that the only way a Rotor Overspeed can become known about is by those responsible being HONEST, sadly sometime Honesty is a very rare commodity.