Robinson control inspection.
 

As it is impossible to inspect the areas of the Robinson cyclic and collective control linkages in the belly pan, and given that there must be fifty metres of wiring in close proximity to the connecting rods and mixer unit. would not a plexiglass panel seem an obvious answer? Or is the pinned on aluminium cover a load carrying component?.

The aluminium panel is screwed in at the rear edge, and fits under a little sticky out bit of metal at the front, whose technical name eacapes me. Rebate ?

It can pop out as a result of a hard landing - the plate that is - and it's not structural.

Robinson control inspection.
 

Thanks for the reply Nr, but its front skid bow panel that is clamped on one side. If as you say even this panel pops out as the result of a hard landing, I think anyone finding this panel displaced would need to check the tubes around the gearbox mounting area. The panel I was referring to, is the long centre panel that has pins all round it. The reason I raised the question was that it seems rediculous to check the visible links around the gearbox and on top of the mast and yet be unable to check the more conjested areas in the belly pan, when for the want of a clear panel this would be simple.

If you incorporated a clear panel, you'd therefore see whats underneath and scare yourself ridged!

Better to leave it as it is:D

What is meant by pins? Rivets? The easily removable longitudinal belly panel is held on by a couple of dozen screws. I suppose if someone laid on a really thick coat of paint then said panel might appear to be attached with rivets (or maybe someone lost the screws and attached it with Cherry's!?). And yes, it is structural:D

Robinson control inspection.
 

Pat Cox. Thanks for the reply, The description "pins" is probably more commonly used here in the UK to describe a method of attatchment. "pinned on" might mean it is fixed by rivets, set pins, bolts, self tappers etc. A bit like we might get the wrong idea if someone said your sisters got a nice little fanny. As you come from Torrance, you dont by any chance work for Robinsons do you. Have a few question about 22 gearboxes , nothing nasty but there is little or no information available here. Regards Bug.

R22 with Floats Just seen in North UK
 

I have just seen a nice shiney new Red and white R22 fully equiped with Floats, flying east into what I think is about a 25Knt head wind, poor little thing it was a struggle to mentain what looked like 40/50 knts air speed, fifteen mins later it came back this time with a tail wind, going like stink towards the West Coast.

Just a short question if you have floats and you are starting up on water, do you need to give full antitorque as soon as the engine/rotors start to pick up, or is it like doing a spot turn ie. a little at a time untill it is just balanced right?

Peter R-B

Full pedal from start, and it will still turn 180 on you !

Indeed I do work for RHC. Time constraints, however, only permit me to check into this forum only once or twice a week. Feel free to ask your question, or direct email RHC Tech Support at [email protected] Fly safely!

Don't I remember reading that starts from cold on water are Not Recommended? Something to do with straining the TR.

There is a R22 Mariner (name?) based at Helicentre Blackpool that matches that description. You may even be able to hire it, then you could have a go on water!!!

SEL - exactly, it is G-YMBO and is not exactly what wfrpilotpb was describing as "shiny new" as it is a 1992 model. Checking the CAA site, I note that at the last CofA issue (21 Sep 01) it still only had 707 hours on it, so I guess Helicentre at Blackpool have bought it to whack 1493 hours on it before it time expires in 2004. Given that it was registered to them in Jan 03, I would venture that they could offer hours on this quite cheaply.

Mind you, if you wanted your own, I noticed that Sloane had a couple of newer (yellow) ones for sale, and there's a silver one which Tiger are leasing that is for sale too.

G-YMBO is currently based at Cranfield (?) Or was a few Months ago.
The owner used it for fishing trips off the Blackpool coast!

He would sit it down in the sea, assemble his fishing rod and stick it out the door!

You should have a close up inspection of it.....
Never seen so much rust!

Not sure if its true, but I remember hearing that upon starting a H500 on the water, it will rotate through 540 degrees before tail rotor takes effect on the torque. Funny if pirates are approaching!:p :E

R22 blades?
 

A question posed on another site.
In this day and age of advanced materials, why havn't RHC got some Composite blades happening? surely they would be a better option than the current ones in the reliability stakes. I would have thought they would wear better and be stronger and have a much longer TBO.
Does any one know if they have looked into this?
If they have looked into it, why was the Idea rejected?

Just curious.

Um. less helicopters falling from the sky due to blade problems maybe????, product liability problems???, selling a product that will be usable after its TBO after inspection????, Inreased profit from a desirable product that cost less to produce????
I don't know actually, thats why I asked. :rolleyes:

(less helicopters falling from the sky due to blade problems maybe????, )

Maybe if the R22 was flown within its limits then there wouldnt be as many accidents due to blades giving up.

However im not against the idea of composite blade technology.

cheers

Thanx Belly tank, maybe theres another advantage, Increasing the limits of the aicraft, enabeling them to be used in other roles.???

Still just curious. ;)







Damn these phat phinga's

Well if your gonna put composite blades on it why not just make it a rigid rotorhead and get rid of the thing everyone complains about? Probably because that goes against the whole R22 philosophy, cheap, light, efficient. Your 180 grand helicopter would probably become 280...probably a gross overestimation but...

The answers quite easy - its because Frank wouldnt make as much money out of selling you blades every couple of thousand hours.

Autorotate.

I think A/spat has the patent on the way composite blades are manufactured (the way they are wound etc).

Might cost Frank a pretty penny to manufacture and set up.

Although I consider the R22 an ideal recreational vehicle, I believe that in the role of training and working it's caperbilities are stretched to close to the limits.
Flown within it's limits and in fine weather the construction is adequate. Metal blades should cope as designed.
The 300 still has metal blades.
So could the problem be that Franks rotor head isn't suitable with the metal blades and Hughes design of fully articulated is OK?

I'm sure it's been discussed and researched at RHC, but then look at the enormous in-house assembly line and custom manufacturing machines. To make a change from metal to composites would require prototypes, testing, certification, new machines, validations, new quality control measures, new procedures, and retraining their entire staff... all read as big $$$ with little ROI. Frank isn't going to do that on an old ship that is already proven... he won't even retrofit blade caps (the ones put on the R44) to the R22.

There is some composite in the R44 blade. This is also a SS skinned item - and the R22 will have similar soon.

New AD on R22
 

A new AD has Just been issued relating to the fatal accident in WA.

The AD requires owners to remove the MR yoke A907 and MR clutch shaft joint A166, and inspect the joint for wear.

The apparent failure of this part has been put forward as the cause of the accident.

It is being said that an incorrect coating was used in the assembly of the componet on this machine.

The correct coating is meant to be straight zinc chromate,
whereas the machine in question (and many others) was assembled using what is commonly referred to as cocky !!!!, a thicker version of the paint that does not dry out.

The two bolts that hold the yoke onto the clutch shaft have sheered off. the theory is that the thicker paint stopped the bolts from reaching the proper torque and over time, allowed the bolts to become loose in the yoke.

The AD requires the shaft and yoke to be disassembled and inspected whithin ten hours active from November 12th.

Cocky Shit??????
 

Here is something to consider. The statement was made that the “Cocky !!!!” version of the Zinc Chromate paint does not dry out. There is a possibility that the paint served as a lubricant on the threads of the bolts in question and instead of the bolts coming loose they were instead overtorqued due to the slippery threads and the bolts sheared due to tensile overstress.

But then again who listens to an old man

:E :E

here it is:

http://www.casa.gov.au/avreg/aircraf...22/R22-051.pdf

[/B]deeper[/B]

Where do you get "broken bolts" out of that?

R22 BETA II Power loss
 

Dear experienced R22-pilots,

together with a student, during a slowly hover-turn to the left, we had an hard landing following a sudden power loss (rpm-drop) in a R22 BETA II. The engine didn't stop.

Conditions:
ALT: 6400ft (pressure altitude)
TEMP: OAT at 47°F/8°C (at 6400ft); dew point about 32°F/0°C.
QNH: 1025hPa
Wind: calm
Weight (TOW): 1316lbs/597kg
Height: 1ft/0.3m above ground

What the Flight Manual says:
In the performance graphic (AFM) it is possible to hover up to 10'000ft/msl (PA) with the conditions (weight, temperature, pressure) we had that day.

What do you think about the power avaible from the engine?
Is this normal?
Should we check the engine?

Thanks for your help.

Question:

Did the low rotor rpm horn sound/warning light illuminate?

Also, you give due point as 'about 0degC.' Suggest you get an aftercast and be more sure of the figure. If the dew point was closer to your OAT - 8degC - and even if it is not, you may have experienced carb-ice.

Ask yourself...was the governor switched on? The governor can mask the build-up of carb-ice in Robinsons by gradually opening the throttle to compensate for the reduced airflow through the carb. You only know you have a problem when it reaches full throttle and the power starts to drop fast.

Carb-ice is also likely if you had recently started the machine from cold?

Having said all that, you were close to max TOW, 1370lb from memory, so the throttle setting in nil wind conditions would already have been near the max, reducing the likelihood of carb-ice. In any case, any power drop, perceived or real, should be checked out thouroughly. Suggest you start with the mags, then the compression. You might have valve trouble or all manner of things. Get it checked by a Lycoming man, and if he's happy get the rest of the machine checked over by a Robo mechanic!

Dan

I don't think carb icing would be a problem in those conditions but without doing the sums I think you just ran out of power.

I've seen a similar thing happen to someone attemping a downwind T/O over a cornfield :rolleyes: Just dropped into the corn.

Did you notice the manifold pressure?

From memory the mtow is about 622kg. So you were hovering heavy at over 6000 ft applying left pedal ???? What do you reckon happened ??

Sir:

With all due respect, two questions:

Do you comprehend the usual response from any helicopter that you have loaded to over 96% of maximum, hovered it at an rather high density altitude, and then practiced *left* pedal turns

How "hard" can any helicopter land *from 12 inches* above the ground with even total power loss. ?
In My Humble Opinion, Instructors often demo hovering autos from that altitude, and even if PIC does nothing (except apply pedal to maintain heading), the helicopter does not land "hard".

Aren't R22 (and R44) engines derated, so even if you were using full power the butterfly valve would not have been fully open, increasing the likelyhood of carb ice?

Russell
1840hrs turbine heli
5 hrs piston heli
so I may be talking out of my ar5e....tell me! :confused:

Possible cause of hard landing
 

Alpinehelicopter,

Perhaps a pertinent question to ask would be; what characterized the terrain over which you were hovering?

If it was long grass or similar, the effects of recirculation could have substantially reduced the ground cushion which resulted in the hard landing you describe.

While by no means the sole cause, it could be a contributing factor.

Kind Regards
Bluegold

Put some time into reading all you can about Carb Icing. You will be surprised to learn that Carb Icing can occur almost anytime. It just needs the right cocktail of ingredients.

R22 B2 Power Loss
 

At that altitude, did you have much carb heat on? Reason i ask is beacuse if you have full carb heat on and give it loads of left pedal, did you sneak by the 25 inches of manifold pressure :{

When was the last maintenance done on the aircraft, and like Bluegold said, what sort of terrain were you hovering over? Did you establish what the Dew point was?

Sorry to ask, but it could all be relevent.

MD 900 :ok:

Overboosted Mr Selfish??

Don't think so. If this robbie had been boosted it would not have hit the ground hard. The turbo would've pressurised the intake and forced atomised particles of air and fuel into the cylinder mimicing the characteristics of sealevel operation.

Since the R22 is not fitted with a turbo this is very impossible. Like you correctly said: the redline is the "derating". The limit is when the collective and the throttle will travel no further in a positive direction.

If this really did end in a hard destructive landing, then it is a sad example of how many people are being taught bad habits early on by inexperienced instructors. Like TMFlyer says.....12 inches is not a long way off the planet.

Carb icing is insidious. It won't end in a sudden power loss but a gradual degradation. In this case being at full throttle would negate this occuring as it usually occurs around the throttle butterfly during a partial open position. Hense why you apply carb heat prior to decent.

Stretching the memory, but with carb icing there is a couple of kinds.

Throttle icing as previously discussed, usually around a partially open throttle as the airflow velocity increases and the pressure drops, cooling the air to freezing.

There is also fuel icing, a cooling effect from the introduction of fuel as it soaks up latent heat energy to vaporise, like when you spill gas on your skin it feels cold. This is downstream of the throttle butterfly and can tip the temperature below freezing.

What I am trying to say is icing can occur in the carby and also downstream in the intake manifold, despite being at full throttle.

'alpinehelicopter' is very quiet!

'Floppy', I gotta tell ya. . :confused:

As you can see from the graph, in those conditions, full throttle is around 23.5"

I don't know why everyones bangin' on about carb icing!

Verdict: Overpitched

http://www.a2b-web.co.uk/pics/PGR22.gif

The last time I was at 9000ft in an R22, I confirmed that the throttle and the collective will come to the end of their travel at the same time. It was mostly a coincidence but interesting none the same. Without the fancy smancy lift formula it is apparent that the MR will bleed off.....:rolleyes:

Mr Selfish: "Over boosting" is a completely wrong term here for what happens when you exceed the redline on an R22. Unfortunately you are one of the many (engineers I have worked with included) who use this term incorrectly. It is the result of poor theory instruction in Aussie. I have never heard the term used elsewhere.

Overboosting is terminology used for super/turbo charged engines indicating that you are exceeding the allowable positive pressurisation of the cylinders for that power/throttle/engine condition. The result is detonation and wear to the piston and cylinder as it opposes the increasing pressure while the piston rises during the compression stroke.

SO! you cannot "overboost" a non-boosted engine....just impossible.

There is no term for using all the engines power and ignoring a little redline. Musterers have been doing it since last century.

The ramifications are increased wear....(maybe) and decreased component times. Despite the redline I know of very few O-520's that make it to a 2200hr overhaul without having new cylinders and pistons fitted.

I think Lu has a term stashed away somewhere for this ......