What about the LIGHT heli needs fixing?
Thread Starter
What about the LIGHT heli needs fixing?
Okay folks,
Nick's thread seems to be dominated by large heli issues, so i thought i'd start a seperate thread for light machines.
FIRSTLY:
SO...what about light helicopters needs fixing guys.....what do you really really want?
SECONDLY:
If the R22 was modified with bigger engine, transn, and Rotor system such that now you could carry 2 x 224lb (16 stone) guys with 400nm of fuel a 40lb of bags, but kept the same purchase price and burned 13gal/hr would it be more use? Would is sell better? Would you buy it?
Cheers
CRAN
Nick's thread seems to be dominated by large heli issues, so i thought i'd start a seperate thread for light machines.
FIRSTLY:
SO...what about light helicopters needs fixing guys.....what do you really really want?
SECONDLY:
If the R22 was modified with bigger engine, transn, and Rotor system such that now you could carry 2 x 224lb (16 stone) guys with 400nm of fuel a 40lb of bags, but kept the same purchase price and burned 13gal/hr would it be more use? Would is sell better? Would you buy it?
Cheers
CRAN
PPRuNe Enigma
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CRAN;
Of course a lot of the answers here are just too easy: we'd all like our helis to be cheaper, have more power, use less fuel and so on. Unfortunately these are usually conflicting requirements and in all designs compromises have to be made.
So here's a couple of practicalities to get things started:
1. Instruments:
For the money, instruments should be much higher quality and not go wrong. How hard can it be to design a fuel gauge that actually works, and horizons etc. that can stand up to a little ham-fistedness from students ? And radios that don't f*ck up if you shut down the engine before they're switched off ? For the money, all these should work from day 1 for the life of the helicopter with little or no maintenance.
2. Carb heat:
Either make it fully manual or have a fuel injected engine that doesn't carb ice. What I don't want is poxy carb heat assist which just results in the control not being in the same position as you left it
[Not much use anyway unless it has time displacement technology and can increase the heat 30 seconds before you reduce power]
.
3. Error-proof:
Following on from 1, and especialy on training aircraft should be a lot harder to inadvertently cause damage by incorrect operation. To take an example: the recent discussion on engine overspeeds. Why is it even possible to rev the engine so high as to cause damage ? Should be easy enough to have a rev limiter or similar.
And easy enough to fit electrical protection to radios etc. so that they can't be damaged.
Of course a lot of the answers here are just too easy: we'd all like our helis to be cheaper, have more power, use less fuel and so on. Unfortunately these are usually conflicting requirements and in all designs compromises have to be made.
So here's a couple of practicalities to get things started:
1. Instruments:
For the money, instruments should be much higher quality and not go wrong. How hard can it be to design a fuel gauge that actually works, and horizons etc. that can stand up to a little ham-fistedness from students ? And radios that don't f*ck up if you shut down the engine before they're switched off ? For the money, all these should work from day 1 for the life of the helicopter with little or no maintenance.
2. Carb heat:
Either make it fully manual or have a fuel injected engine that doesn't carb ice. What I don't want is poxy carb heat assist which just results in the control not being in the same position as you left it
[Not much use anyway unless it has time displacement technology and can increase the heat 30 seconds before you reduce power]
.3. Error-proof:
Following on from 1, and especialy on training aircraft should be a lot harder to inadvertently cause damage by incorrect operation. To take an example: the recent discussion on engine overspeeds. Why is it even possible to rev the engine so high as to cause damage ? Should be easy enough to have a rev limiter or similar.
And easy enough to fit electrical protection to radios etc. so that they can't be damaged.
But then it would be a jetranger or something....not a Robby!
Cool as a moosp
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Good differentiation from the heavy metal that is answering Nick's post. I don't mean to have a go at any light helicopter in particular but my (in)experience may show which I fly.
1. Can we please get rid of Magnetos? They are a pain to maintain and are such a dated technology that it is embarrassing to talk with auto engineers about them.
2. Ditto carburetors. The auto world also threw them out years ago. Carb icing still kills pilots and passengers every year.
3. Also can we have overhead cam engines that do not need two minutes run down time to cool the valve guides? I haven't needed a two minute rundown on my auto since my 1954 Jowett Javelin. (Pleasant twinge of nostalgia there, Mmm.)
4. Water cooled engines are generally quieter. I appreciate that at small scale they may be heavier.
5. Jet A1 is cheaper in many places, and diesel technology may give a 25% range increase.
Beyond Nicks allowed five points...
6. A service interval of 50 or 100 hours is indicative of a mechanical system working at its limit. If European auto manufacturers can give a 15,000 mile service interval (perhaps 300 hours at 50 mph...) can we at least look at increasing the service interval for new engine/airframes.
7. As Grainger pointed out, it should be impossible to overspeed the engine. An inexpensive rev limiter is fitted to many high performance auto engines and saves embarrasing rebuilds. (I once put a rod through the side of an auto engine at around 7500 rpm. Blame youthfull excess, but I then fitted a limiter.)
8. Fenestrons do scale down. They are quieter, safer in the amateur environment of light helicopters and are getting lighter.
9. Five point harness in the smallest of machines. OK with luck and skill I will never need it but I still feel more comfortable with them.
9. Despite several requests on the 'other' thread I do not need a cup holder. At my experience level I have yet to chew gum and fly.
For my two cents worth, I guess it all comes down to certification costs, but a diesel R44 would be a seriously competitive machine.
1. Can we please get rid of Magnetos? They are a pain to maintain and are such a dated technology that it is embarrassing to talk with auto engineers about them.
2. Ditto carburetors. The auto world also threw them out years ago. Carb icing still kills pilots and passengers every year.
3. Also can we have overhead cam engines that do not need two minutes run down time to cool the valve guides? I haven't needed a two minute rundown on my auto since my 1954 Jowett Javelin. (Pleasant twinge of nostalgia there, Mmm.)
4. Water cooled engines are generally quieter. I appreciate that at small scale they may be heavier.
5. Jet A1 is cheaper in many places, and diesel technology may give a 25% range increase.
Beyond Nicks allowed five points...
6. A service interval of 50 or 100 hours is indicative of a mechanical system working at its limit. If European auto manufacturers can give a 15,000 mile service interval (perhaps 300 hours at 50 mph...) can we at least look at increasing the service interval for new engine/airframes.
7. As Grainger pointed out, it should be impossible to overspeed the engine. An inexpensive rev limiter is fitted to many high performance auto engines and saves embarrasing rebuilds. (I once put a rod through the side of an auto engine at around 7500 rpm. Blame youthfull excess, but I then fitted a limiter.)
8. Fenestrons do scale down. They are quieter, safer in the amateur environment of light helicopters and are getting lighter.
9. Five point harness in the smallest of machines. OK with luck and skill I will never need it but I still feel more comfortable with them.
9. Despite several requests on the 'other' thread I do not need a cup holder. At my experience level I have yet to chew gum and fly.
For my two cents worth, I guess it all comes down to certification costs, but a diesel R44 would be a seriously competitive machine.
Iconoclast
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2+1= fewer problems
If we are addressing the Robinson line I would advise that they design a three-blade rotor system similar to the Schweizer 300. This particular rotorhead was not designed by Hughes but was adapted from an autogyro. From what I understand Frank Robinson worked for Hughes around the time of the design of the Hughes 269 and most likely designed his own rotor system for the R-22 to prove that he could. If a 3-blade system with full articulation were installed on the R-22 and R-44 they would be screamers and most of the limitations placed on them relative to mast bumping and extreme flapping would go away. If the 3-blade system were adapted at the onset there would be no FAA AD 95-26-04 and there would be many people still living and flying.
Iconoclast
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The drum needs banging.
To: Grainger
3-blade system =:
Ability to fly in zero G situations.
No restrictions regarding side slip and out of trim flight.
No mast bumping.
I think that is a drum that needs banging.
3-blade system =:
Ability to fly in zero G situations.
No restrictions regarding side slip and out of trim flight.
No mast bumping.
I think that is a drum that needs banging.
Senis Semper Fidelis
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How light is light , though? like a lot of people I was taught on the R22 and thought it brilliant, I progressed onto the R44 and was very, very impressed, went onto the B206 and find that I would willingly barter my delightful wife for part ownership in one, have flown a friends Gazelle and get damp in certain areas.
If I didnt have a leg iron I would go for the Gazelle, but to be totally practical the B206 would have to be the target, I feel that the R22, albeit a very good machine would be still a trifle risky for the family silver to be carried in!!
If I didnt have a leg iron I would go for the Gazelle, but to be totally practical the B206 would have to be the target, I feel that the R22, albeit a very good machine would be still a trifle risky for the family silver to be carried in!!
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Never mind the bloody rev limiter. One great thing about the R22 is that when you're on the limit, there's still a couple of inches left to bail you out; in the Hughes you'd haul on the lever, get the low RPM light and dive for the bushes.
Nobody's mentioned the biggest menace to helicopter acceptance, which is noise. External noise, the kind that winds up the punters and gets them on their hind legs angrily declaiming against the excesses of overprivilege.
Nobody's mentioned the biggest menace to helicopter acceptance, which is noise. External noise, the kind that winds up the punters and gets them on their hind legs angrily declaiming against the excesses of overprivilege.
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Noise is mainly a perception issue.
The same folks who complain about aircraft noise are probably quite happy to spend their Sunday mornings driving a petrol mower around their gardens at much higher dB and duration than an overflying aircraft
Jealousy perhaps ?
The same folks who complain about aircraft noise are probably quite happy to spend their Sunday mornings driving a petrol mower around their gardens at much higher dB and duration than an overflying aircraft
Jealousy perhaps ?
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To Lu, 
Going from a 2-blade to a 3-blade rotor will overcome some problems, but it will create others. Two that come to mind are;
1/ an reduction in the allowable load
2/ a greater possibility of ground resonance.
To Noise,
Noise comes high on the list of both threads. The following article from Rotor & Wing ~ May 2002 may be of interest to those who have not already read it. Public Acceptance: The Noise Threshold: Is Quieter Better?
Going from a 2-blade to a 3-blade rotor will overcome some problems, but it will create others. Two that come to mind are;
1/ an reduction in the allowable load
2/ a greater possibility of ground resonance.
To Noise,
Noise comes high on the list of both threads. The following article from Rotor & Wing ~ May 2002 may be of interest to those who have not already read it. Public Acceptance: The Noise Threshold: Is Quieter Better?
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I think mostly of training aircraft when I think of small helicopters. To improve them, there should be a FDR of some sort that creates a very complete record of the previous flight. Use it for debriefing and confirming that limits weren't exceeded.
Training aircraft should have training limits that allow the student to fly the entire syllabus safely. There should also be the 'other' limits for when the student screws up. Build this into the aircraft.
Going away from the non-training side of light helicopters, I say set everything up to be as single person operation as possible. Hands on C&C, single point refuelling (and open cell just in case), avionics designed for same, baggage and tool capacity for self-deployability, DI's made clear for pilots (ie: panels located right in front of things to examine, fluid level gauges idiot-proof, etc.)
The other thing I always wonder would be a benefit would be self-levelling skids. I know, it seems kinda weird, but if you could control the angles and heights of the skids, maybe split them for even more control, and all without a weight penalty, maybe off-levels and rough area landings would be more safe.
My ideas come from seeing, reading and/or hearing about small helicopter accidents. The number one cause is human frailties (I'm cautious to call them all errors). Procedures, training, and watchdogs NOT helicopter design is what we really need to fix that.
Training aircraft should have training limits that allow the student to fly the entire syllabus safely. There should also be the 'other' limits for when the student screws up. Build this into the aircraft.
Going away from the non-training side of light helicopters, I say set everything up to be as single person operation as possible. Hands on C&C, single point refuelling (and open cell just in case), avionics designed for same, baggage and tool capacity for self-deployability, DI's made clear for pilots (ie: panels located right in front of things to examine, fluid level gauges idiot-proof, etc.)
The other thing I always wonder would be a benefit would be self-levelling skids. I know, it seems kinda weird, but if you could control the angles and heights of the skids, maybe split them for even more control, and all without a weight penalty, maybe off-levels and rough area landings would be more safe.
My ideas come from seeing, reading and/or hearing about small helicopter accidents. The number one cause is human frailties (I'm cautious to call them all errors). Procedures, training, and watchdogs NOT helicopter design is what we really need to fix that.
