Autorotation: Hitting the spot
Chief Bottle Washer
Originally Posted by birddog
SAS, could you please elucidate what you mean by the above for those of us who are less erudite than yourself?
As SASless said (about auto RPM checks), there is an auto RRPM checking procedure within the maintenance manual for nearly all helicopters.
Basic procedures are to set a stable auto at flat pitch (minimum collective) and datum IAS, then record at a specific Density Altitude the aircraft weight, OAT and RRPM (and maybe one or two other parameters). After landing a check with the appropriate graph in the MM will give the target auto RRPM for that height and temperature which is corrected for weight. Compare target auto RRPM to the recorded auto RRPM, and adjust equally all blades to increase/decrease auto RRPM. Repeat check flight until autorotation RRPM is within set parameters.
If the helicopter isn't set up iaw the manufacturer's auto RRPM specs, you'll be chasing your tail trying to perfect your auto technique, IMO. You may have either a high auto RRPM or worse, very low auto RRPM, and be unable to get the required autorotational performance from your helicopter.
SASless, I am still waiting for your answer to the question I asked of you.
Here it is again:
If you can't answer this, shall I presume you don't know?
Your whole argument falls over if some poor bugger just happens to be flying a machine that isn't correctly rigged (and/or is overloaded...) and does shed a blade at the end of the flare, snapping his neck in a nanosecond. He is still dead even if he's a foot off the ground. After all, it is probably the poorly maintained helicopter that is more likely to fail.
By the way, the answer to the long list of questions that you fired back at me (how DARE I question you!), is YES for all of them.
Here it is again:
SASLess, can you tell me exactly at what point the rotor system will let go in an overspeed, so I know just how much overspeed at the bottom of an auto I can accept and get away with?
Your whole argument falls over if some poor bugger just happens to be flying a machine that isn't correctly rigged (and/or is overloaded...) and does shed a blade at the end of the flare, snapping his neck in a nanosecond. He is still dead even if he's a foot off the ground. After all, it is probably the poorly maintained helicopter that is more likely to fail.
By the way, the answer to the long list of questions that you fired back at me (how DARE I question you!), is YES for all of them.
Last edited by the coyote; 28th Jun 2010 at 22:23.
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Mmmm ....
My how the thread changes .... by missing just half a day of posts .....
I was seriously shocked to read 'hueyracer's' post re Auto RPM adjustment ...
I will give him the benefit of the doubt with regard language ..... but now have a worry about the standard of maintenance pilot training in the German Military.
Without putting on my 'Maintenance Engineers' hat I must say that Auto RPM checks post maintenance are probably of the most important checks to be done on a rotorcraft.
Those that have ever changed a machine over from/to fixed float configuration will know that the 'Auto Revs' change quite dramatically and definitely need to be correctly re-rigged IAW the maintenance manual ...
In fact you will find somewhere in the RFM (& Maint manual) there will be a 'minimum aircraft (flying) weight' which is all about ensuring that a 'correctly rigged' and configured aircraft WILL be able to get into 'safe steady state autorotation' ... it is I believe a certification requirement.
Can we now stop concerning 'rabid cat' any further!
My how the thread changes .... by missing just half a day of posts .....
I was seriously shocked to read 'hueyracer's' post re Auto RPM adjustment ...
I will give him the benefit of the doubt with regard language ..... but now have a worry about the standard of maintenance pilot training in the German Military.
Without putting on my 'Maintenance Engineers' hat I must say that Auto RPM checks post maintenance are probably of the most important checks to be done on a rotorcraft.
Those that have ever changed a machine over from/to fixed float configuration will know that the 'Auto Revs' change quite dramatically and definitely need to be correctly re-rigged IAW the maintenance manual ...
In fact you will find somewhere in the RFM (& Maint manual) there will be a 'minimum aircraft (flying) weight' which is all about ensuring that a 'correctly rigged' and configured aircraft WILL be able to get into 'safe steady state autorotation' ... it is I believe a certification requirement.
Can we now stop concerning 'rabid cat' any further!
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sasless is writing the same words that i say to pilots, that in a real emergency situation life it is better to have too much rpm that too little.
coyote, no ones having a go at you, we are just expressing opinions as you said yourself. nobody said to have massive overspeeds, all that has been said is that it is better to be a bit high than to be obsessed with limits when the situation is not looking good.
pilot to boss; yes boss i wrecked the machine but i made sure the rpm was in the green, i was adjusting it as i went in.
sasless has been around a long time and i am sure it is because he is a very practical pilot and not a pedantic, the same as i try to be and i think we will be around a lot longer because of that fact.
coyote, no ones having a go at you, we are just expressing opinions as you said yourself. nobody said to have massive overspeeds, all that has been said is that it is better to be a bit high than to be obsessed with limits when the situation is not looking good.
pilot to boss; yes boss i wrecked the machine but i made sure the rpm was in the green, i was adjusting it as i went in.
sasless has been around a long time and i am sure it is because he is a very practical pilot and not a pedantic, the same as i try to be and i think we will be around a lot longer because of that fact.
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Senior Pilot, thanks for the reply.
Reading what you posted, it makes perfect sense; what does not make perfect sense (to me), is why this is not taught as part of the PPL or CPL syllabus (at least never taught to me).
One could argue this is more relevant than some of the other course material.
...honest Mr Instructor, the only reason I was hunting after the RRPM in that last practice auto was because this helicopter was not calibrated correctly for autos
One learns something new every day!
Reading what you posted, it makes perfect sense; what does not make perfect sense (to me), is why this is not taught as part of the PPL or CPL syllabus (at least never taught to me).
One could argue this is more relevant than some of the other course material.
...honest Mr Instructor, the only reason I was hunting after the RRPM in that last practice auto was because this helicopter was not calibrated correctly for autos
One learns something new every day!
imabell, I couldn't agree with you more. I am a big believer in being practical, and I am not about crashing a machine while trying to keep it in within limits if it can be saved otherwise.
I guess what I am putting forward is rather than say "you can never have too much RRPM" why not say "it is crucial that you manage your RRPM effectively at all times". One tends to make a pilot ignore it, one tends to make a pilot give it the due attention that it rightly deserves.
I too have done a lot of autos, and I have gone to the ground with the engine silent (twice), and I too would prefer more RRPM at the end than not enough if I had the choice. But it can be easily achieved without spinning it off the clocks on the high side.
If what SASless is saying is right, then why don't the manufactures say in a genuine emergency, you can never have too much RRPM?
I guess what I am putting forward is rather than say "you can never have too much RRPM" why not say "it is crucial that you manage your RRPM effectively at all times". One tends to make a pilot ignore it, one tends to make a pilot give it the due attention that it rightly deserves.
I too have done a lot of autos, and I have gone to the ground with the engine silent (twice), and I too would prefer more RRPM at the end than not enough if I had the choice. But it can be easily achieved without spinning it off the clocks on the high side.
If what SASless is saying is right, then why don't the manufactures say in a genuine emergency, you can never have too much RRPM?
Chief Bottle Washer
Originally Posted by birddog
Reading what you posted, it makes perfect sense; what does not make perfect sense (to me), is why this is not taught as part of the PPL or CPL syllabus (at least never taught to me).
One could argue this is more relevant than some of the other course material.
One could argue this is more relevant than some of the other course material.
This is probably only the first of many, and I'm pleased that Rotorheads may have helped you.Most companies (and the military) will tend to use more experienced pilots to address maintenance issues on flights, for obvious reasons: they will have the knowledge to properly analyse anomalies and assist rectification of faults in post flight discussions with the ginger beers. Even the proper logging of engine power assurance figures on a regular basis is a skill that is not always taught during training, but a chat with your instructor to ask for advice on how to may reap great benefits. Not the least, it will show your enthusiasm and willingness to learn
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Disregard everything after good morning....
The way senior pilot wrotes it is EXACTLY the way we are doing it..
So i have to admit-i DID understand you wrong...
The auto-r-rpm is checked to stay within specific limits.....and if it isn´t, you will adjust the settings..
Within the military, we FIRST tune the rotor in powered flight...thereafter follows that (under normal conditions) the system is balanced perfectly so no more adjustments have to be made for auto-r-rpm.....
We just check it-and in 9 of 10 cases there are no further adjustments necessary..
Hopefully we are NOW talking about the same....?
The way senior pilot wrotes it is EXACTLY the way we are doing it..
So i have to admit-i DID understand you wrong...
The auto-r-rpm is checked to stay within specific limits.....and if it isn´t, you will adjust the settings..
Within the military, we FIRST tune the rotor in powered flight...thereafter follows that (under normal conditions) the system is balanced perfectly so no more adjustments have to be made for auto-r-rpm.....
We just check it-and in 9 of 10 cases there are no further adjustments necessary..
Hopefully we are NOW talking about the same....?
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You would be hard pressed to run the rotor RPM up to the point where it would start to come apart. Drag increase due to RPM will, at some point, become self-limiting.
You may do some long term damage to the components, and damage that might make it necessary to replace the dynamic components for no other reason that they haven't been tested or proven beyond a reasonable speed, but I doubt you'd ever overspeed anything to the point of immediate failure during your real autorotation.
The only catastrophic failure I know of related to speed was due to an engine runaway from idle (65% to 117% in two seconds) that severed the tail rotor driveshaft because of the sudden surge in torque (more than just speed).
Has anyone ever heard of an overspeed that was catastrophic?
You may do some long term damage to the components, and damage that might make it necessary to replace the dynamic components for no other reason that they haven't been tested or proven beyond a reasonable speed, but I doubt you'd ever overspeed anything to the point of immediate failure during your real autorotation.
The only catastrophic failure I know of related to speed was due to an engine runaway from idle (65% to 117% in two seconds) that severed the tail rotor driveshaft because of the sudden surge in torque (more than just speed).
Has anyone ever heard of an overspeed that was catastrophic?
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To summarise lets take the simplistic R22 Beta model.
Empty weight say 861lbs.(FROM MY pfm)
Minimum allowable Gross weight to drive the rotor system is 920 lbs.
Think for one second, when will the aircraft enter the EOL phase says inventor Frank. Right the aircraft is full of oil, with a pilot and a dumb ass pilot at that who has used all of the fuel, so calculate as follows;
empty weight plus minimum allowable pilot weight with doors off, 135lbs. = 996lbs.
Min AUW for safe EOL is 920lbs, hey presto we are safe.
Mother nature, that's good ol gravity, will therefore turn the rotors fast enough to have a happy downward flight and successful termination.
Franks' engineers will have also provided that at the minimum ROD that is possible, as long as the aircraft is not overloaded. At this point we say 'Thank you Frank'.
I have only said thank you Frank three times, although that may have been mixed with blasphemy about his bloody drive belts or upper bearings, but there are many times I have said Thank you to Arthur. He was a top dude.
Now when checking auto RRPM always have the collective on the bottom,
it says so in the book but no one has said it here yet.
You will find that there will be a straight line variation pretty much between
- RRPM at minimum Power off RRPM limit (90%) at that minimum weight, and
- RRPM at top of RRPM limit power off (110%) at max AUW. You can look at the Maintenance Manual chart or work it out on the back of an envelope.
The engineer will adjust as necessary.
What no one else has said here so far is that by following the book as above you will be blessed with the full collective lever available to apply at the bottom to slow things down, isn't that great?
Because if you were a damm fool or a know it all and had the auto RRPM set too high for a reason known only to yourself you would have the collective some ways up at high weight to maintain it in the green, or at a low weight you might have had it right down with RRPM right up at the top of the green.
In each event you will have given yourself a higher ROD than necessary and certainly a lot less collective to pull at the bottom.
Dumb eh?
I could put my final edit in here and say that the higher the ROD that you have the more collectiove you will need and also the harder it will be to learn the basics. REAL, REAL DUMB EH?
Besides every thing else that is said here and I will argue with anyone, high ROD regardless of the RRPM at the time, is what kills, maims and hurts, work and study at getting it low.
That is not to say that during EOL flight you may occasionally encounter slightly high RRPM, turning for example especially towards the gyroscopic precession direction, or during a tight flare. Trees a bit close you know, that sort of thing.
No, as others have said don't worry about that too much but report it each time to the engineers. I had the dubious luxury of owning an aircraft once (R22) that had the spindle bearings replaced after 300 hours of instruction including autos. They were close to failing be jeeesus, so don't do it if it can be avoided the MM book knows best.
That's pretty much it.
But I will finish with a quote from a previous and famous Chief Pilot of ours from many moons ago, who sent a scathing Teletype message to a renowned and famous Bell pilot based in Cairns many years ago after being real p**ssed off with the auto RRPM set up on a machine that he tested upon delivery to us.
The message? "it would have real good RRPM upon impact". Go figure.
Learn the basics from the book and worry about the complexities later.
cheers tet
Empty weight say 861lbs.(FROM MY pfm)
Minimum allowable Gross weight to drive the rotor system is 920 lbs.
Think for one second, when will the aircraft enter the EOL phase says inventor Frank. Right the aircraft is full of oil, with a pilot and a dumb ass pilot at that who has used all of the fuel, so calculate as follows;
empty weight plus minimum allowable pilot weight with doors off, 135lbs. = 996lbs.
Min AUW for safe EOL is 920lbs, hey presto we are safe.
Mother nature, that's good ol gravity, will therefore turn the rotors fast enough to have a happy downward flight and successful termination.
Franks' engineers will have also provided that at the minimum ROD that is possible, as long as the aircraft is not overloaded. At this point we say 'Thank you Frank'
. I have only said thank you Frank three times, although that may have been mixed with blasphemy about his bloody drive belts or upper bearings, but there are many times I have said Thank you to Arthur. He was a top dude.
Now when checking auto RRPM always have the collective on the bottom,
it says so in the book but no one has said it here yet.
You will find that there will be a straight line variation pretty much between
- RRPM at minimum Power off RRPM limit (90%) at that minimum weight, and
- RRPM at top of RRPM limit power off (110%) at max AUW. You can look at the Maintenance Manual chart or work it out on the back of an envelope.
The engineer will adjust as necessary.
What no one else has said here so far is that by following the book as above you will be blessed with the full collective lever available to apply at the bottom to slow things down, isn't that great?
Because if you were a damm fool or a know it all and had the auto RRPM set too high for a reason known only to yourself you would have the collective some ways up at high weight to maintain it in the green, or at a low weight you might have had it right down with RRPM right up at the top of the green.
In each event you will have given yourself a higher ROD than necessary and certainly a lot less collective to pull at the bottom.
Dumb eh?
I could put my final edit in here and say that the higher the ROD that you have the more collectiove you will need and also the harder it will be to learn the basics. REAL, REAL DUMB EH?
Besides every thing else that is said here and I will argue with anyone, high ROD regardless of the RRPM at the time, is what kills, maims and hurts, work and study at getting it low.
That is not to say that during EOL flight you may occasionally encounter slightly high RRPM, turning for example especially towards the gyroscopic precession direction, or during a tight flare. Trees a bit close you know, that sort of thing.
No, as others have said don't worry about that too much but report it each time to the engineers. I had the dubious luxury of owning an aircraft once (R22) that had the spindle bearings replaced after 300 hours of instruction including autos. They were close to failing be jeeesus, so don't do it if it can be avoided the MM book knows best.
That's pretty much it.
But I will finish with a quote from a previous and famous Chief Pilot of ours from many moons ago, who sent a scathing Teletype message to a renowned and famous Bell pilot based in Cairns many years ago after being real p**ssed off with the auto RRPM set up on a machine that he tested upon delivery to us.
The message? "it would have real good RRPM upon impact". Go figure.
Learn the basics from the book and worry about the complexities later.
cheers tet
Quick post then got to run....
I chatted with Hueyracer by PM....it was more a language issue than technical....he is working in his second language.
I submitted an earlier post that seems to have gotten lost in the ether....which would have answered several questions posted by Birddog and others.
Since then...several folks have responded with explanations very similar to my lost post.
I will post again when I get back from introducing my almost foster daughter to the nice friendly Army Recruiter....she shows some interest in taking up helicopter flying although I would prefer to see her learning languages, the Law, or most anything else rather than helicoptering!
I chatted with Hueyracer by PM....it was more a language issue than technical....he is working in his second language.
I submitted an earlier post that seems to have gotten lost in the ether....which would have answered several questions posted by Birddog and others.
Since then...several folks have responded with explanations very similar to my lost post.
I will post again when I get back from introducing my almost foster daughter to the nice friendly Army Recruiter....she shows some interest in taking up helicopter flying although I would prefer to see her learning languages, the Law, or most anything else rather than helicoptering!
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Having done literally (tens of) thousands of "full ons" over a 35 year career.....I am appalled that "any instructor" would not nurture and hone a basic survival skill of "hitting the spot" ????
No matter what terrain, in any part of the world, under any condition(s), it is an "ESSENTIAL" survival skill, whether ab initio, or an exprienced pilot.
No matter what terrain, in any part of the world, under any condition(s), it is an "ESSENTIAL" survival skill, whether ab initio, or an exprienced pilot.
I have been reading this thread for a while, but never had time to respond. I think we are getting mixed up between training autos and real life autos. Other than to repeat the excellent words of Sasless--"Ass, tin, ticket", this is all I have to say on this point.
I will share a publication I acquired some years ago entitled "How to crash a helicopter". It gives you the advice that you always wanted to know but were too afraid to ask, for example; "what if I have nowhere to go but into the trees?" (see page 8)
How to crash a helicopter
Going back to the original question posed by rabidcat:
I have taught the occasional auto in my time, and all I can say is....give it time. There is a ton of excellent advice on this thread, but in reality, it will just "click" one day. You need to read, listen and watch all about autos, and then find what works for YOU. Do not beat yourself up over not hitting the spot right away. Like Sasless, I am not a "numbers" or "theory" type pilot. I see myself more as a kinesthetic type pilot---as in feel the aircraft---trust me, it will come to you one day. I have had students ask me how I did certain things with the helicopter---I cannot explain it, but I can demonstrate so YOU can feel it----and then you can hopefully mimic until you can do it yourself. Hopefully you have an instructor who can do this for you.
Think of it this way----try to explain to me, HOW you balance while riding a bicycle? Some things just come with practice and feel.
I will share a publication I acquired some years ago entitled "How to crash a helicopter". It gives you the advice that you always wanted to know but were too afraid to ask, for example; "what if I have nowhere to go but into the trees?" (see page 8)
How to crash a helicopter
Going back to the original question posed by rabidcat:
I just can't seem to accurately judge the spot I am aiming for. I know most everyone has had this problem when they were learning, is it just repetition or is there some other trick?
Think of it this way----try to explain to me, HOW you balance while riding a bicycle? Some things just come with practice and feel.
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I am a bit embarrassed to ask this, but what is this "Ass, tin, ticket" bit that you all speak of? I am sure it is quite obvious but let's pretend for a moment that I am just not all that sophistomicated 
.
And once more, thank you all for the help. I am following the thread and absorbing what I can. My instructor ok-ed the chinagraph pen idea... so we are making progress. When weather clears up and I am back to normal flying instead of checkride prep and ground I will give that a try to start.
.And once more, thank you all for the help. I am following the thread and absorbing what I can. My instructor ok-ed the chinagraph pen idea... so we are making progress. When weather clears up and I am back to normal flying instead of checkride prep and ground I will give that a try to start.
"Ass, tin, ticket"
1. Save your "Ass", as in yourself.
2. Save the "tin", as in the aircraft.
3. Save your "ticket", as in your license.
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, but what is this "Ass, tin, ticket"
And the beautiful 'almost' has NOT been allowed to have it explained to her by all us all straight up and down real nice honest blokes as to why "helicopteuring" is a downright reputable profession.
why don't you ask him why he didn't invite her to meet us.
betcha y' get the same response as above.
Mug of Tea in hand....AFD texting away on her phone....new kitty sacked out on the floor after mooching the Commodore's chow....said Commodore having a royal snit fit about the "evil woman" and her feline consort....back on board here.
Gordy is exactly right about the "Ass, Tin, Ticket" concept of priorities. The sole objective of helicopter flying is for the Pilot and Passengers to be able to hit the bar upon termination of the flying day. One accomplishes that by using the aircraft as a reusable container for important items (said crew and pax). While carrying out that evolution (Navy Term applied to doing something), the concern about whether it is legal or not is of the very least importance. So..."Ass"....get them all home safely with as few aches and pains as possible, "Tin"...preserve the aircraft as long as possible as the Boss Fellah likes for his investment to last as long as possible in the very best of condition....but if needed...use every penny of his money to accomplish save yer "Ass"! As to "Ticket"....worry about arguing with the Crats Agin Aviation after you recover from the "Glad to be Alive" Party. Their snide tidings amount to naught in the scheme of things as compared to "Ass and Tin".
TET described an Auto Revs airtest well enough....and the same general procedure applies to all aircraft. I reference the autorev chart in the Maintenance Manual and calculate the "Target Nr" prior to the flight. Then conduct the flight to ensure I hold a stabilized descent for a full One Thousand-Two Thousand feet of height, with the Collective Lever FULL DOWN (if possible) and record the OAT, Altitude, and Nr. If adjustments are required....do another flight until the target Nr is achieved (or as close as possible) as there might be some slight variation.
As to introducing my AFD to a helicopter pilot.....Forgetaboutit!
Gordy is exactly right about the "Ass, Tin, Ticket" concept of priorities. The sole objective of helicopter flying is for the Pilot and Passengers to be able to hit the bar upon termination of the flying day. One accomplishes that by using the aircraft as a reusable container for important items (said crew and pax). While carrying out that evolution (Navy Term applied to doing something), the concern about whether it is legal or not is of the very least importance. So..."Ass"....get them all home safely with as few aches and pains as possible, "Tin"...preserve the aircraft as long as possible as the Boss Fellah likes for his investment to last as long as possible in the very best of condition....but if needed...use every penny of his money to accomplish save yer "Ass"! As to "Ticket"....worry about arguing with the Crats Agin Aviation after you recover from the "Glad to be Alive" Party. Their snide tidings amount to naught in the scheme of things as compared to "Ass and Tin".
TET described an Auto Revs airtest well enough....and the same general procedure applies to all aircraft. I reference the autorev chart in the Maintenance Manual and calculate the "Target Nr" prior to the flight. Then conduct the flight to ensure I hold a stabilized descent for a full One Thousand-Two Thousand feet of height, with the Collective Lever FULL DOWN (if possible) and record the OAT, Altitude, and Nr. If adjustments are required....do another flight until the target Nr is achieved (or as close as possible) as there might be some slight variation.
As to introducing my AFD to a helicopter pilot.....Forgetaboutit!
@ coyote:
I realize much of this is remedial, but I respond to you for the benefit of our OP.
In the helicopters I flew, letting Nr Run a bit too high in autorotative descent tended to increase Rate of Descent, a problem which will have to be dealt with in the flare and final pull/recovery. Then again, if you have a very tight landing zone, that may be a good tactic on a given autorotative descent. (Won't get into the esoterics of slips and unbalanced flight, no point at the moment).
This characteristic would make the generic mantra of "you can never have too much Nr" suspect, when you are trying to make the helicopter perform.
Controlling Nr and Airspeed isn't an academic exercise. It is intended to keep the speed and rate of descent manageable as you attempt to hit a safe landing spot, and also to keep your rotor system in the sweet spot so you have the most margin for error. Likewise, with a few extra turns, flight controls being linked to rotor performance, no point losing fore and aft, and lateral, control before necessary as the NR decays in the final input(s).
In support of SASless general comment, letting NR zoom/incr in the flare is generally OK, but only if doing so doesn't detract from your ability to brake the rate of descent in preparation of the final input that allows you to land safely (hopefullyl upright) on the ground/sea where you intended to.
In practice autos, overspeeding NR pisses off the maintenance folks due to added inspections, and I IIRC over time it can shorten component life. That irritates the boss who paid for the bird ...
In a real auto, where the engines or TR quit, there are larger fish to fry than yet another inspection cycle.
All said and done, I somewhat agree with your reservations on the NR comment, but we probably ought to spell out why, and in what flight regime.
I realize much of this is remedial, but I respond to you for the benefit of our OP.
In the helicopters I flew, letting Nr Run a bit too high in autorotative descent tended to increase Rate of Descent, a problem which will have to be dealt with in the flare and final pull/recovery. Then again, if you have a very tight landing zone, that may be a good tactic on a given autorotative descent. (Won't get into the esoterics of slips and unbalanced flight, no point at the moment).
This characteristic would make the generic mantra of "you can never have too much Nr" suspect, when you are trying to make the helicopter perform.
Controlling Nr and Airspeed isn't an academic exercise. It is intended to keep the speed and rate of descent manageable as you attempt to hit a safe landing spot, and also to keep your rotor system in the sweet spot so you have the most margin for error. Likewise, with a few extra turns, flight controls being linked to rotor performance, no point losing fore and aft, and lateral, control before necessary as the NR decays in the final input(s).
In support of SASless general comment, letting NR zoom/incr in the flare is generally OK, but only if doing so doesn't detract from your ability to brake the rate of descent in preparation of the final input that allows you to land safely (hopefullyl upright) on the ground/sea where you intended to.
In practice autos, overspeeding NR pisses off the maintenance folks due to added inspections, and I IIRC over time it can shorten component life. That irritates the boss who paid for the bird ...
In a real auto, where the engines or TR quit, there are larger fish to fry than yet another inspection cycle.
All said and done, I somewhat agree with your reservations on the NR comment, but we probably ought to spell out why, and in what flight regime.
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Sassy, you're name is not Leroy Jethrow Gibbs is it? 