Hey FAA,...you missed one! :-)
You use the placard to see what your max MAP is. If when you lift to the hover, you have the same MAP - you have zero performance margin. This should correlate with your assessment of AUM and density altitude on the IGE and OGE hover graphs. If you think you are well under the MAUM for IGE or OGE hover according to the graphs and you are still pushing the MAP limit in the hover then either check your figures or call the engineer.
BR--It would seem you did not read my post #17 above very carefully. Without the requisite performance data in the POH, how am I to do this? I'd really like to know!
https://robinsonheli.com/r44-ii-poh/
https://robinsonheli.com/r44-ii-poh/
Pulling into a hover gives you a delta.
Robinson are kind enough to provide hover performance charts like any other manufacturer.
What else is needed?
If you plan to stick to the performance limitations provided, leave a little margin for error and fly with a degree of accuracy (preferably into wind), you're not about to exceed the performance envelope.
I see Crab beat me to it.
Lets say you are at 1300lbs in a R22HP, you can operate IGE up to 8500’ PA in standard atmosphere and OGE up to 6,500’ PA in standard atmosphere.
To operate at OGE at 8,500 in the same conditions, you would need to reduce your AUM by 100 lbs.
So if you are at 1200 lbs you can operate at 8,500 but you still only just have OGE.
If you now reduce your AUM further by 5% (60lbs) or 10% (120lbs) of that OGE AUM, you have a thrust margin which will get you out of trouble and allow you to manouevre OGE with some degree of safety.
All this assumes you are at or under your max MAP in the hover.
It might be academic since the POH shows you can't get much more than 6,000 PA ISA standard at the limiting MAP.
To operate at OGE at 8,500 in the same conditions, you would need to reduce your AUM by 100 lbs.
So if you are at 1200 lbs you can operate at 8,500 but you still only just have OGE.
If you now reduce your AUM further by 5% (60lbs) or 10% (120lbs) of that OGE AUM, you have a thrust margin which will get you out of trouble and allow you to manouevre OGE with some degree of safety.
All this assumes you are at or under your max MAP in the hover.
It might be academic since the POH shows you can't get much more than 6,000 PA ISA standard at the limiting MAP.
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Both of you gentlemen are infuriating.
You tell me to do "A".
I tell you "A" is not possible.
So, when you realize this is the case, then you come back and tell me to do "B" as if it is an answer to how to do "A", and then sit back smugly in front of the PC.
You do this all the time.
Why do you do that? It's either intellectual dishonesty or you gents are just getting too old.
Answer the original question, I dare you: you tell me to calculate the MP in a hover for conditions of flight. I tell you the data is not int the POH to make that calculation. How do I calculate it for a Robinson R44? Looking up the max. continuous or 5 minute max. allowable MP's are not correct answers.
Must enter the real world now. Back later to see how this works out...
You tell me to do "A".
I tell you "A" is not possible.
So, when you realize this is the case, then you come back and tell me to do "B" as if it is an answer to how to do "A", and then sit back smugly in front of the PC.
You do this all the time.
Why do you do that? It's either intellectual dishonesty or you gents are just getting too old.
Answer the original question, I dare you: you tell me to calculate the MP in a hover for conditions of flight. I tell you the data is not int the POH to make that calculation. How do I calculate it for a Robinson R44? Looking up the max. continuous or 5 minute max. allowable MP's are not correct answers.
Must enter the real world now. Back later to see how this works out...
Calm down, calm down.
No, Robinson don't provide you with a means for calculating your MAP in the hover.
However, you can confirm that you are under the AUM for IGE and OGE hover for your operating conditions (presuming you know your PA and OAT).
If you are under the AUM from the both the graphs then, as long as you are in the hover at less than your MCP figure from the placard, you should have a half decent performance margin.
You can work out roughly how much by looking at the MAUM for OGE at your selected operating altitude - lets say you are at 6000 ft PA and plus 30 deg C OAT and hit the 2200lbs GW line on the graph. If you are at 2200lbs you have OGE but no performance margin, for every 220lbs you are under that AUM, you gain a 10% thrust margin. That sounds like a lot but it is probably enough power to overcome light turbulence or achieve a couple of hundred fpm RoC in the hover.
At lower density altitudes you will have more performance and should never get close to MAP limits unless you are ham fisted.
The problems come when pilots do not calculate their AUM and C of G correctly and do not check they are under the weights for IGE or OGE hover at their planned operating altitude.
It's not our fault Robinson don't give you better performance graphs btw.
No, Robinson don't provide you with a means for calculating your MAP in the hover.
However, you can confirm that you are under the AUM for IGE and OGE hover for your operating conditions (presuming you know your PA and OAT).
If you are under the AUM from the both the graphs then, as long as you are in the hover at less than your MCP figure from the placard, you should have a half decent performance margin.
You can work out roughly how much by looking at the MAUM for OGE at your selected operating altitude - lets say you are at 6000 ft PA and plus 30 deg C OAT and hit the 2200lbs GW line on the graph. If you are at 2200lbs you have OGE but no performance margin, for every 220lbs you are under that AUM, you gain a 10% thrust margin. That sounds like a lot but it is probably enough power to overcome light turbulence or achieve a couple of hundred fpm RoC in the hover.
At lower density altitudes you will have more performance and should never get close to MAP limits unless you are ham fisted.
The problems come when pilots do not calculate their AUM and C of G correctly and do not check they are under the weights for IGE or OGE hover at their planned operating altitude.
It's not our fault Robinson don't give you better performance graphs btw.
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Originally Posted by [email protected]
No, Robinson don't provide you with a means for calculating your MAP in the hover.
However, you can confirm that you are under the AUM for IGE and OGE hover for your operating conditions (presuming you know your PA and OAT).
I'd rather slag on Robinson for the meager data in the POH than deal with this crazy fetish for misdirection you have. And you know how "protective" I am of Robinson
Thread Starter
Originally Posted by [email protected]
There's no need to flounce off Robbie - I was trying to make a serious point which seems forgotten in the argument - settling with power is to do with performance (or lack of it) but VRS is purely an aerodynamic condition.
How many Robinson pilots calculate their expected hover MAP and maximum MAP before they go flying? How many lfit to the hover and don't check to see if the expected MAP is the same as their actual MAP and then wonder why there might be a difference.
Now try coming to an OGE hover when your engine isn't performing properly or your blades are dirty (or even both) - you were expecting to have that performance but it's not there and you start to descend, immediate reaction is to raise the lever - cue Nr decay as the engine maxes out and an unwanted descent which, if you are lucky, will stop as ground effect saves you. You have just setlled with power but were not in IVRS or VRS.
That is why it is important to understand the difference, to make pilots aware that you must know your expected performance BEFORE you go flying rather than finding out the hard way.
The problem is, you can exceed your MAP and there are no flashing lights or klaxons in the cockpit so it is easily ignored but you are slowly trashing your engine.
How many Robinson pilots calculate their expected hover MAP and maximum MAP before they go flying? How many lfit to the hover and don't check to see if the expected MAP is the same as their actual MAP and then wonder why there might be a difference.
Now try coming to an OGE hover when your engine isn't performing properly or your blades are dirty (or even both) - you were expecting to have that performance but it's not there and you start to descend, immediate reaction is to raise the lever - cue Nr decay as the engine maxes out and an unwanted descent which, if you are lucky, will stop as ground effect saves you. You have just setlled with power but were not in IVRS or VRS.
That is why it is important to understand the difference, to make pilots aware that you must know your expected performance BEFORE you go flying rather than finding out the hard way.
The problem is, you can exceed your MAP and there are no flashing lights or klaxons in the cockpit so it is easily ignored but you are slowly trashing your engine.
Look, if you want to call having HOGE problems because of engine trouble and/or dirty blades "settling with power" then well,...bully for you!
The whole point of this fiasco is that the FAA has abandoned that term all together, yet in their effort to, "erase Moses' name from all of history", they missed one little inscription.
,...and I found that funny.
So, take it the wrong way, take offense, take unbridge, look down your noses at the "poorly trained Robbie pilot", I've seen it all before, knock yourselves out,..I just wish I had more whip cream for my cocoa!
Look, if you want to call having HOGE problems because of engine trouble and/or dirty blades "settling with power" then well,...bully for you!
Thread Starter
Originally Posted by [email protected]
I guess you are not getting it. If you don't have enough power to hover OGE and you try anyway then you will end up sinking and decaying the RRPM - is that clear enough?
Now you have lost me completely........
But there you go again. Why the extended discourse on something that a) is only tangentially relevant to the original issue, and b) is something that every helicopter pilot needs to demonstrate prior to getting their first license or certificate and therefore should go without saying? Why this compelling need to embellish something along a tangent? It's as if you want to obfuscate the fact that you had to, didn't want to, or couldn't answer the original question or issue. It's bizarre
I am required by law to calculate my aircraft performance if I am flying commercially and by other regulations if I am flying military - No-one is watching GA pilots, some of whom just treat their aircraft like a truck, put in it what they like and then get airborne without considering the implications.
If my tedious lengthy discourse makes one GA pilot pause and consider how they are approaching flying in a cavalier manner - it will be worth your ire.
