do all R44s have throttle governors ?
Interesting thought! It is this one https://www.jetphotos.com/photo/keyword/G-ODOC R44 Astro S#0372
Not saying the pilot didn't use full carburetor heat before descending but if he didn't, then on short final, the 'throttle valve' could have been partly blocked with ice, restricting fuel flow, the throttle will open more and more to desperately try to get more fuel flowing (hence why it's a good thing to keep your hands on the throttle so you can identify it if you missed it on the gauges).
All speculation of course but it is a rumour network.
fwiw I've never had the slightest trouble hearing the low RPM horn - and a good job too. I've flown with Bose A20 and Lightspeed Zulu and PFX, and the same applies to all of them. It is LOUD, as indeed it should be.
I was wondering about the remark concerning the way to hold the collective/throttle too. I've always been taught to hold it just behind the throttle, with just thumb and forefinger on the throttle.
The place where I did my heli primary lost an R22 to a soloing student who heard the low RPM and instantly went into autorotation - good. But she rolled the landing, end of R22, though luckily she was unhurt. My instructor (and hers) said that he'd noticed she had a tendency to over-control the throttle...
I was wondering about the remark concerning the way to hold the collective/throttle too. I've always been taught to hold it just behind the throttle, with just thumb and forefinger on the throttle.
The place where I did my heli primary lost an R22 to a soloing student who heard the low RPM and instantly went into autorotation - good. But she rolled the landing, end of R22, though luckily she was unhurt. My instructor (and hers) said that he'd noticed she had a tendency to over-control the throttle...
To my knowledge the R44 Astro has a carburetor......and it surely was cold that day.....
Not saying the pilot didn't use full carburetor heat before descending but if he didn't, then on short final, the 'throttle valve' could have been partly blocked with ice, restricting fuel flow, the throttle will open more and more to desperately try to get more fuel flowing (hence why it's a good thing to keep your hands on the throttle so you can identify it if you missed it on the gauges).
All speculation of course but it is a rumour network.
Not saying the pilot didn't use full carburetor heat before descending but if he didn't, then on short final, the 'throttle valve' could have been partly blocked with ice, restricting fuel flow, the throttle will open more and more to desperately try to get more fuel flowing (hence why it's a good thing to keep your hands on the throttle so you can identify it if you missed it on the gauges).
All speculation of course but it is a rumour network.
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One is, as you might guess, that I prefer people to be able to twist the throttle without having to first reposition their hand, for instance in order to do a hovering auto ( if the tail rotor fails in a hover ). You also can't turn the governor off without first having to reposition your hand.
The other reason is that the R44 collective is already sensitive and moving your hand onto the metal tube makes it even more so. If that's not clear, I mean that the more you slide your hand toward the attachment end of the tube, the less mechanical advantage you have. This means you have to use more force to move the collective, while trying to move it a shorter distance. It's my personal belief that this can cause (student) pilots to over control the collective. It's a small difference, but I think noticeable.
In the end, you should do whatever works for you. It's just a personal preference, but those are the reasons I don't like our students to be taught that method.
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I actually feel pretty strongly that the warning horn should be carried by the intercom/headset... the word "criminal" comes to mind given the prevalence of noise canceling headsets in use these days... You shouldn't ever have to struggle to hear that warning system over background noise... Whether it's music, screaming passengers ( from fear or fun ) or radio traffic, that warning should be LOUD.
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As for R22s, I learned in R22 standards and HPs. By the time I was taking lessons, they all had tip weights, but a friend who started 2-3 years before me remembers flying the standards without tip weights. There were no rotor brakes or aux fuel tanks, and none of our aircraft had any gyro instruments. Oh yeah, no voice activated intercom, you had to use the push buttons, which Robinson must have paid $0.01 for, because they never worked. The lack of governors increased the CFI's workload considerably ... Basically the instructor WAS the governor, we would always be tweaking the RPM to keep it in the green. The green range was something like 97-104 but students would have excursions all the time, so we would have to keep an eye on the RPM.
We had the #2 R22, N32AD at our school. It's now in the Smithsonian. It had already been converted to an HP when I was flying it. The cockpit was an inch or two narrower than all other R22s, which made it difficult to do hover autos from the left seat if the door was on... Your wrist would get jammed against the door. You had to do a two step motion... Roll the throttle to idle, reposition your hand, roll the throttle the rest of the way into the override...
When the R22 governor was first introduced, it would move the collective. This sounds like a good idea... It could actually lower the collective to recover RPM. It actually sucked, and was soon replaced by the R44 governor design which only moved the throttle.
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The earlier R44 (Raven I) are all carburated, only the Raven II have fuel injections. Problem with the carburated ones is that the governor compensates carb ice until the throttle is fully open with no indication to the pilot except the turning of the throttle grip. Rpm and manifold pressure remain static until there is no throttle way left. Once the rpm drops, you are in deep trouble as the engine may not provide enough heat anymore to clear the manifold. We flew all carbed Robinsons with the carb heat on when outside temp was below 15 degrees C. Fuel guzzling but safe.
As long as you do your job managing carb heat per the relevant POH, R22 or R44 (and they are different in this area, so go read carefully), you should not have a problem. Just like you shouldn't have a problem in any other carb-equipped piston engine aircraft. Get behind the power curve (hah, a pun!) on your carb heat management and you could have a problem. I'm not sure when it came into use, but newer R22 and R44's have a carb heat assist system that helps manage the carb heat. See Section 4 in the Raven I POH. Also Safety Notice 25.
This is one thing about the G2 that I am jealous of, which is the electronic, automatic carb heat system on that aircraft. It would be very nice to see a similar system on the R22 and R44 Raven I's, and a power limit indicator to go along with it. I've heard rumors that Robinson is working on electronic engine instrumentation. That would be a very welcome addition since Robinson has already fully embraced Garmin glass and Genesys HeliSAS for those willing to pay for it.
You can still buy Raven I's, it's still a current model.
As long as you do your job managing carb heat per the relevant POH, R22 or R44 (and they are different in this area, so go read carefully), you should not have a problem. Just like you shouldn't have a problem in any other carb-equipped piston engine aircraft. Get behind the power curve (hah, a pun!) on your carb heat management and you could have a problem. I'm not sure when it came into use, but newer R22 and R44's have a carb heat assist system that helps manage the carb heat. See Section 4 in the Raven I POH. Also Safety Notice 25.
This is one thing about the G2 that I am jealous of, which is the electronic, automatic carb heat system on that aircraft. It would be very nice to see a similar system on the R22 and R44 Raven I's, and a power limit indicator to go along with it. I've heard rumors that Robinson is working on electronic engine instrumentation. That would be a very welcome addition since Robinson has already fully embraced Garmin glass and Genesys HeliSAS for those willing to pay for it.
As long as you do your job managing carb heat per the relevant POH, R22 or R44 (and they are different in this area, so go read carefully), you should not have a problem. Just like you shouldn't have a problem in any other carb-equipped piston engine aircraft. Get behind the power curve (hah, a pun!) on your carb heat management and you could have a problem. I'm not sure when it came into use, but newer R22 and R44's have a carb heat assist system that helps manage the carb heat. See Section 4 in the Raven I POH. Also Safety Notice 25.
This is one thing about the G2 that I am jealous of, which is the electronic, automatic carb heat system on that aircraft. It would be very nice to see a similar system on the R22 and R44 Raven I's, and a power limit indicator to go along with it. I've heard rumors that Robinson is working on electronic engine instrumentation. That would be a very welcome addition since Robinson has already fully embraced Garmin glass and Genesys HeliSAS for those willing to pay for it.
Gordy, I was responding to the title "all R44", not all Robinsons... I didn't remember that the Astro R44 started without a governor. There were not a lot of R44 on the east coast, I don't remember, but Robinson was probably limiting R44 sales to the west coast at first.
As for the HP---we all loved it because it made touchdown autos a breeze with the battery in the nose.
As for low PM--the R-22 will still maintain directional control in the hover at 70% RPM---it was a demonstration we did with all student pilots. People tend to frak out these days with low RPM---I think over the years there has been a scare tactic. Same with Low G----that used to be allowed and was a required maneuver for the CFI check ride.
As for low PM--the R-22 will still maintain directional control in the hover at 70% RPM---it was a demonstration we did with all student pilots. People tend to frak out these days with low RPM---I think over the years there has been a scare tactic. Same with Low G----that used to be allowed and was a required maneuver for the CFI check ride.
The purpose of the demonstration was to instill confidence and fine tuning in the throttle...freaking out is not good....just gently and smoothly wind it back on.....
,...or does it not really stall at 80?
Nah....I think you mis-read my post. I said the demonstration is done on the hover......and the purpose was to show the effectivness of the TR and to get the student to manipulate the throttle slowly with purpose, without freaking out.
The stall you refer to would be on the retreating side, and to be honest I have not worked out the math to determine the percentage it would stall at, but there would be many factors---primarily forward speed.
The stall you refer to would be on the retreating side, and to be honest I have not worked out the math to determine the percentage it would stall at, but there would be many factors---primarily forward speed.
Nah....I think you mis-read my post. I said the demonstration is done on the hover......and the purpose was to show the effectivness of the TR and to get the student to manipulate the throttle slowly with purpose, without freaking out.
The stall you refer to would be on the retreating side, and to be honest I have not worked out the math to determine the percentage it would stall at, but there would be many factors---primarily forward speed.
The stall you refer to would be on the retreating side, and to be honest I have not worked out the math to determine the percentage it would stall at, but there would be many factors---primarily forward speed.
I will consult my texts then.
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I flew with one person who described a demo a cfi gave him where they flew around the pattern at 70%... The problem being that if the engine had failed, the rotor would have stalled no matter how fast the collective had been lowered.
Of all the interesting things to explore in helicopter aerodynamics, this is one corner of the envelope I've never been tempted to play in...
I flew with one person who described a demo a cfi gave him where they flew around the pattern at 70%... The problem being that if the engine had failed, the rotor would have stalled no matter how fast the collective had been lowered.
Go try this, I assume you have access to an R-22: Establish a stabilized 2 foot hover, turn off the governor and SLOWLY wind down the throttle to 70%, (and I mean SLOWLY), as you do, you will be constantly adding collective and left pedal. Then slowly wind throttle back on again---repeat a few times till you are comfortable. Worse case if you screw it up, you will just settle to the ground, at which point start again.
I am certainly NOT trying to get you to go outside your comfort zone, but merely trying to expand your comfort zone in a safe manner. Feel free to do this with an instructor, (forgive me if you are one---I do not know).
Hopefully you will learn something and feel better about it---I try to learn something new every day.
For the person who flew a traffic pattern at 70%---- I am sorry there are bad CFI's out there----I echo 212man's comment---"Stay well clear of this person".
Last edited by Gordy; 3rd Jan 2020 at 15:58. Reason: Spelling