I've only done a couple autos with my instructor and when you're doing them you don't realize how much is going on great video can't wait to see the next one thank you!
My instructor also said that damage to the rotor bearings and attachment bolts will occur due to the higher blade speeds higher centrifugal forces. Great videos by the way😃
Thanks for the great videos ! Can you please elaborate on your experience with extending your glide to reach the touchdown point, as well as being too close, and cutting down on the horizontal glide distance - Thanks !
Generally the closer you are to Max Endurance airspeed the more time aloft you have. As you get closer to Max Range airspeed, you increase the distance travelled but you’ll also increase your rate of descent. Most operators manuals preach doing autos midway between these 2 points. But you can use these airspeeds to your advantage depending on the altitude you have and the touchdown point you need to make it to.
@@helicopterlessonsin10minut10 Thanks ! Will be great to see a video discussing S turns, Slip and zero speed, so you can hit your spot.... Thanks again !
Really nice and helpful Video! However I am not sure if I understood the decent rate to knots thing right. Shouldn’t the Formula be FPM/100 instead of FPM*100? 3000FPM/100 = 30 Or did I understand something wrong? But yeah, superb quality, as always!
I have a great video idea for you. How would an Army Aviator go about getting their civilian helicopter and commercial license. Test, certs, costs, etc.
Go right outside the Daleville gate at Ft. Rucker to the Professional Helicopter Pilot Association. Bring your flight records also. They’ll go through the study guide and give the test. Takes a couple of hours and costs less than $100 from what I remember. It’s super quick and painless.
So not sure if you remember me. But I finally took the sift this morning. Needed a 40 and got and got a 62. Def thought I was gonna fail halfway through. Thank you for all your help.
@@helicopterlessonsin10minut10 so for me I organized the 7 sections in priority for me personally 1. Aviation knowledge 2. Math 3. Mechanical Comprehension 4. Spatial apperception 5. Hidden figures 6. Paragraph comprehension 7. Simple shapes. I’ll def say the more time to study the better. I studied for 2-3 Months. I started with the FAA Manual (which was very dense and hard to read at times in understanding) which is how I discovered you on RUclips. I’d recommend reading through the manual and people following your videos as they read it. And then reading it again. Then creating flash cards. This helped tremendously. Along with the other books you recommended for practice tests. And watching your videos again for clarification. At times I had to watch the same video 3-4x for it to register but it being
Hey Jacob, how do left and right turns have a different rate of increase when in an auto? In your transient torque video you state that the increase is due to more or less induced flow over the back and front of the rotor disk and which way the Gyroscopic precession is acting. But in an autorotation there should be no induced flow present once the airflow changes to an upwards pattern instead of downwards pattern? Thanks for the videos.
Great question! When in a forward airspeed auto, the autorotative regions (stall, driving, driven) shift slightly more to aft and to the retreating side of the rotor. This causes differential drag across the disk like transient torque. When applying lateral cyclic, these pitch increases and decreases compresses/expands driving and driven regions. When turning left, this would increase pitch over the tail (driven region expands, driving region contracts) and decrease over the nose (driving expands, driven contracts). This would normally slow the rotor but because the total aerodynamic force (TAF) shifts from vertical vector, the aircraft falls faster and the upflow overwhelms this force into a net effect of a slight increase in rotor RPM. When turning right, the pitch increase is over the nose (+driven , -driving) while the pitch is reduced over the tail (-driven, +driving). This would cause an increase in rotor rpm. Combined with the shifting of the TAF from a vertical vector caused the rotor to increases as well. Net effect is left turns cause a little rotor increase, right turns cause a rapid rotor increase. I hope this helps answer your question.
@@helicopterlessonsin10minut10 Thanks for the quick response. I didn't realize the change in the pitch would have a net effect on the rotor since it would increase the driving in half and reduce in the other half I figured it would all even out to remain a constant and the only increase would be from the total reaction in all states. Thank you for your help.
Usually you save all of the collective until after the flare. But if you want to maintain rotor within limits because it’s getting too high you could mildly increase collective earlier to keep the rotor in check.
Very interesting video and so far everything makes sense for me. At least in this description. But I saw other explanations that contained I think different information. For example many people say (if I understand them right) that during autorotation RPM can be maintained and even accelerated with positive pitch in normal flight. This makes no sense to me. As far as I understood this video you do not claim anything like that. But still I wonder how it would work even with neutral pitch, because there still will be friction etc. that should dangerously slow the rotor. Also I do not understand how this for example is relevant for gyrocopters and their form of locomotion and this would interest me a lot. I would be very interested in your description of how gyrocopters fly. Please excuse my english, it is not my mother tongue. And also I am no real helicopter pilot only a rc helicopter pilot and in our instructions usually no one even mentions neutral pitch, because usually several degree negative pitch are recommended for autorotation. I can not get my head around the claim that there is something that significantly different when it comes to real size helicopters. I mean at least the same principles should be applieable and not completely reversed. I know that real helicopters have different geometrie especially on the rotorhead (like washout etc.) but things like that do not explain the common descriptions of the regions in the rotor during Autorotation (Driving-, driven- region and stall) and sometimes even seem to contradict it. I would be thankful if someone could explain this to me.
Positive pitch in an autorotative state will absolutely decay rotor RPM. The positive pitch used to create lift creates drag as well. With no engine power, the drag without thrust in the rotor blades would cause the rotor to slow. The only way to maintain rotor RPM would be to have neutral pitch. The only way to increase rotor RPM would be negative pitch.
More specifically you want to maintain rotor rpm within normal operating limits. It should have been in this range before engine failure unless something drooped it prior.
random question but I'm searching for advise from vets. Did you ever feel sort of guilty for not going into the infantry? I'm in highschool with a strong interest in army aviation and infantry both, but feel as if that if I tried to go the aviation route, I'd feel as if I'm cheating out on the ones that would be more "involved" in the fight and would feel guilty in a sense. Not sure if that made any sense, just looking for insight.
Not guilty at all. Most of my combat missions were providing air coverage for guys on the ground. Those guys definitely have it tough. But in the air you provide so much in the form of security. Not to mention in an Apache you can smoke an enemy platoon in seconds who are trying to mess with my guys on the ground trying to get some sleep.
Spencer, I’m prior AF CCT and decided on that route over aviation for many reasons other than it was a best fit for my desires and I had an amazing career. I’m now a student pilot in the civilian world so there are different paths to get there. If you want to fly more and get some infantry appreciation…volunteer for airborne with a follow on to Ranger school. National Guard pre ranger course is good route of entry. Good luck and hope you earn the honor of serving in the military.
So, forward cyclic, slows Nr, but increases airspeed... Aft cyclic, increases Nr, but slows airspeed Yet, High Nr, rotor speed increases descent rate... Main point here is: You better have sufficient altitude to have a good glide to descent ratio, otherwise you are gonna have a hard landing...
I've only done a couple autos with my instructor and when you're doing them you don't realize how much is going on great video can't wait to see the next one thank you!
Hey Jacob thanks a lot! I'm on a IP course right now and the videos tell me how do I have to explain things.
Looking forward more videos!
I’m studying now for my sift and this cleared up a major block in my head on how autorotations work, great content!
My instructor also said that damage to the rotor bearings and attachment bolts will occur due to the higher blade speeds higher centrifugal forces. Great videos by the way😃
The videos that cover the broad scope of helicopters (experimental to military) are my favorite. So a special thank you for this one (and part one).
Hey ALL, reading the description on this video is a good use of time. Jacob wrote down some great material there.
Fun fact: all my videos have extensive description sections.
This clarified so much for me. I'm watching out for the 3rd edition. I'm sure there will be way more eye opening explanations. Thanks Jacob.
A man that’s dedicated to teaching 🙌🏽
Thanks for the great videos ! Can you please elaborate on your experience with extending your glide to reach the touchdown point, as well as being too close, and cutting down on the horizontal glide distance - Thanks !
Generally the closer you are to Max Endurance airspeed the more time aloft you have. As you get closer to Max Range airspeed, you increase the distance travelled but you’ll also increase your rate of descent. Most operators manuals preach doing autos midway between these 2 points. But you can use these airspeeds to your advantage depending on the altitude you have and the touchdown point you need to make it to.
@@helicopterlessonsin10minut10 Thanks ! Will be great to see a video discussing S turns, Slip and zero speed, so you can hit your spot.... Thanks again !
is it fpm x 100? so you're saying if i'm a 300 fpm rate of decent = 30,000knots or was that a mistype? I'm thinking it was divide. Love you vids btw
You’re correct. I misspoke. Sorry about the confusion.
Really nice and helpful Video!
However I am not sure if I understood the decent rate to knots thing right.
Shouldn’t the Formula be FPM/100 instead of FPM*100?
3000FPM/100 = 30
Or did I understand something wrong?
But yeah, superb quality, as always!
Yeah, I caught that too .
Good catch. Sorry about that. But yeah divide by 100 for vertical velocity
I have a great video idea for you. How would an Army Aviator go about getting their civilian helicopter and commercial license. Test, certs, costs, etc.
Go right outside the Daleville gate at Ft. Rucker to the Professional Helicopter Pilot Association. Bring your flight records also. They’ll go through the study guide and give the test. Takes a couple of hours and costs less than $100 from what I remember. It’s super quick and painless.
So not sure if you remember me. But I finally took the sift this morning. Needed a 40 and got and got a 62. Def thought I was gonna fail halfway through. Thank you for all your help.
Awesome! Congrats. What would you recommend for others who are about to take the test?
@@helicopterlessonsin10minut10 so for me I organized the 7 sections in priority for me personally
1. Aviation knowledge
2. Math
3. Mechanical Comprehension
4. Spatial apperception
5. Hidden figures
6. Paragraph comprehension
7. Simple shapes.
I’ll def say the more time to study the better. I studied for 2-3 Months. I started with the FAA Manual (which was very dense and hard to read at times in understanding) which is how I discovered you on RUclips.
I’d recommend reading through the manual and people following your videos as they read it. And then reading it again. Then creating flash cards. This helped tremendously. Along with the other books you recommended for practice tests. And watching your videos again for clarification. At times I had to watch the same video 3-4x for it to register but it being
Great feedback. Thanks for lending the time. Congrats again!
Keep making these awesome videos
Hi jacob thanks a lot .
Can you explain with details why NR increase during turning lift with a counterclockwise helicopter ?
Thank you! These videos are a massive help in my studies
Hey Jacob, how do left and right turns have a different rate of increase when in an auto? In your transient torque video you state that the increase is due to more or less induced flow over the back and front of the rotor disk and which way the Gyroscopic precession is acting. But in an autorotation there should be no induced flow present once the airflow changes to an upwards pattern instead of downwards pattern? Thanks for the videos.
Great question! When in a forward airspeed auto, the autorotative regions (stall, driving, driven) shift slightly more to aft and to the retreating side of the rotor. This causes differential drag across the disk like transient torque. When applying lateral cyclic, these pitch increases and decreases compresses/expands driving and driven regions.
When turning left, this would increase pitch over the tail (driven region expands, driving region contracts) and decrease over the nose (driving expands, driven contracts). This would normally slow the rotor but because the total aerodynamic force (TAF) shifts from vertical vector, the aircraft falls faster and the upflow overwhelms this force into a net effect of a slight increase in rotor RPM.
When turning right, the pitch increase is over the nose (+driven , -driving) while the pitch is reduced over the tail (-driven, +driving). This would cause an increase in rotor rpm. Combined with the shifting of the TAF from a vertical vector caused the rotor to increases as well. Net effect is left turns cause a little rotor increase, right turns cause a rapid rotor increase. I hope this helps answer your question.
@@helicopterlessonsin10minut10 Thanks for the quick response. I didn't realize the change in the pitch would have a net effect on the rotor since it would increase the driving in half and reduce in the other half I figured it would all even out to remain a constant and the only increase would be from the total reaction in all states. Thank you for your help.
another interesting thing worth noting is that counter rotating helicopters in autorotation have there yawing inputs reversed.
Does Collective down generally mean the rotor blades have a neutral pitch? & Collective up raises the pitch of the blades?
You got it right
Flying Gyro copters, i think better helps helicopter pilots with auto-rotation situations, very very well, doesn't it ?
Hey Jacob when would you pull collective on a full down auto? Also do you flare without pulling collective?
Usually you save all of the collective until after the flare. But if you want to maintain rotor within limits because it’s getting too high you could mildly increase collective earlier to keep the rotor in check.
Very interesting video and so far everything makes sense for me. At least in this description. But I saw other explanations that contained I think different information. For example many people say (if I understand them right) that during autorotation RPM can be maintained and even accelerated with positive pitch in normal flight. This makes no sense to me. As far as I understood this video you do not claim anything like that. But still I wonder how it would work even with neutral pitch, because there still will be friction etc. that should dangerously slow the rotor. Also I do not understand how this for example is relevant for gyrocopters and their form of locomotion and this would interest me a lot. I would be very interested in your description of how gyrocopters fly.
Please excuse my english, it is not my mother tongue. And also I am no real helicopter pilot only a rc helicopter pilot and in our instructions usually no one even mentions neutral pitch, because usually several degree negative pitch are recommended for autorotation. I can not get my head around the claim that there is something that significantly different when it comes to real size helicopters. I mean at least the same principles should be applieable and not completely reversed. I know that real helicopters have different geometrie especially on the rotorhead (like washout etc.) but things like that do not explain the common descriptions of the regions in the rotor during Autorotation (Driving-, driven- region and stall) and sometimes even seem to contradict it.
I would be thankful if someone could explain this to me.
Positive pitch in an autorotative state will absolutely decay rotor RPM. The positive pitch used to create lift creates drag as well. With no engine power, the drag without thrust in the rotor blades would cause the rotor to slow. The only way to maintain rotor RPM would be to have neutral pitch. The only way to increase rotor RPM would be negative pitch.
@@helicopterlessonsin10minut10 can you make a video on factor a b and c
Good on ya mate nice work.
Okay so when you start an autorotation you are just trying to maintaining the rotor rpm that you had before you lost your engine?
More specifically you want to maintain rotor rpm within normal operating limits. It should have been in this range before engine failure unless something drooped it prior.
I cannot understand for the life of me, how can a rotor spin if the collective pitch is negative of zero? The whole drive/driven part confuzes me.
random question but I'm searching for advise from vets. Did you ever feel sort of guilty for not going into the infantry? I'm in highschool with a strong interest in army aviation and infantry both, but feel as if that if I tried to go the aviation route, I'd feel as if I'm cheating out on the ones that would be more "involved" in the fight and would feel guilty in a sense. Not sure if that made any sense, just looking for insight.
Not guilty at all. Most of my combat missions were providing air coverage for guys on the ground. Those guys definitely have it tough. But in the air you provide so much in the form of security. Not to mention in an Apache you can smoke an enemy platoon in seconds who are trying to mess with my guys on the ground trying to get some sleep.
Spencer, I’m prior AF CCT and decided on that route over aviation for many reasons other than it was a best fit for my desires and I had an amazing career. I’m now a student pilot in the civilian world so there are different paths to get there. If you want to fly more and get some infantry appreciation…volunteer for airborne with a follow on to Ranger school. National Guard pre ranger course is good route of entry. Good luck and hope you earn the honor of serving in the military.
So, forward cyclic, slows Nr, but increases airspeed...
Aft cyclic, increases Nr, but slows airspeed
Yet, High Nr, rotor speed increases descent rate...
Main point here is: You better have sufficient altitude to have a good glide to descent ratio,
otherwise you are gonna have a hard landing...
Really wish you wouldn't use those bloody pens. Teeth are on edge the whole time!
If I pass my sift on Tuesday I'm naming my first born Jacob... Regardless of gender.
Haha! Awesome!
let me know how you do! Good Luck!
I got a 70. Guess you're gonna be a godfather
Congrats man! I guess congrats to me as well lol