There are some youtubers who have the incredible gift of being able to incite viewers from one video to the next in an incessant cycle of wonder and learning. Paul Harrel and Agent Jay Z are two that come to mind. And this gentleman. I continue to wonder at the vast array of special conditions involved in helicopter flight. This particular one is modeled to some degree in Microsoft flight sim but most of them are not and I lament that. For that non-zero number of people who mostly enjoy flight in a simulator but have the privilege of the occasional taste of the fruit of actual flight, it's a disservice to not model these various conditions so they command with some level of confidence and knowledge of limitations. I do a lot of fancy pants things in simulation that I have little to no idea if I could actually get away with, how close to disaster I am, etc. I would like to fly fancy pants, but within the limits of what reality would allow. And Microsoft doesn't do a very good job of identifying and enforcing those limits. I may be a very small minority of simulator pilots that care about that which is probably why Microsoft doesn't dedicate a lot of resources towards it. Anyway, all this to say good job, enjoying your array of lessons.

You are the teachers teacher, most could learn from your teaching abilities to convey information.

Always keep coming back to these.

We’ll done Jacob. Informative and clear as per your habitual style. We feel pampered. Thanks a million

Awesome series! Thank you so much! Huge help

Another great video, Jacob. Keep them coming!

Great video. I really enjoy your concise teaching style. Keep em coming!

I wish he would bring back his video, preparing SIFT as part of a warent packet and these videos have been invaluable

Thanks again sir, looking forward to the next lesson!

Great video, thanks so much, I admire your Job, keep going, excellent explanation, I asked for this video, I was waiting for

Great Vid Jacob. Thank You so Much

Awesome as always sir.

Nice job on this series. 👍🏻🚁

Nice, 150 seconds and I knew why the DCS hind rewards going to fast with banking left into the ground :D

Great video.thank you so much

I’m late to the party but these videos are a huge help! Thanks

Great refresher vidro

Good vídeo ! 👍🏾🚁

Very well explained. Thanks….

Really like these videos great job! Could you do a video more in depth on the aerodynamics of autos? I've seen diagrams showing different lift components but I'm having trouble wrapping my head around why an upward airflow would drive the blades if they are pitched up. Thanks and keep up the good work!

Thanks Jacob ..

Thankyou so much..,I want many more about its transmission

Can you please explane the difference between negative stall and negative lift and positive stall and positive lift? Thank you.

Great lessons more plse

Very informative series thanks. Could you explain the counter rotating blades. All i can find is the cancellation of torque, Can they turn 360 degree? Auto-rotation? etc.

You are my hero

Could you please make a video about transient TRQ?

I had always thought the ONLY issue was with extreme high airspeed causing the advancing blade tip to go supersonic resulting in a loss of lift on that side, but I was wrong.

As a private pilot, unfortunately, a stall may have occurred in Sikorsky helicopter accident.. involving former basketball ball player, Bryant.

Interesting information but, if you were to lower the collective after a violent uncomanded pitch increse due to the stall, the rpm would go crazy

thaaaank you for these videos!!! my instructor just doesn't know how to get some concept across in class and you can do it in 10 minutes. your literally getting me through my cpl haha. thanks man!!

So. I don’t see where you explained why the speed induces the stall. Because the retreating blade too slow compared to the relative wind?

To prepare for my SIFT for the Army I have read the "Helicopter Flying Handbook" (FAA-H-8083-21A) cover to cover would you be able recommend which chapters I should focus my studies on?

Thanks!! :)

what about phase lag and how it's fully recognized at the 6 o clock pos. good video but you didn't say why the helicopter rolls to the left.

I feel like every pilot has a worst fear. Well maybe some don't maybe some say that their worst fears what everyone else is worst fear is getting into one of the bad situations a helicopter can get into. This one is definitely mine. I've never been able to explain why. The main two reasons though that I can think of why this is the most terrifying scenario for me the first one is that it's something we can't go practice. Everything else we can basically practice. I mean aside from this and mast bumping and Low G pushover. But can we practice Auto rotations? Yes. Can we practice hover autos? Yes. Can the instructor purposely leave the alternator off on the startup and then not allow the students to take off and then explain to them they need to go reread the Poh to understand why taking off with the alternator is such a bad idea? Yes. Can we practice IFR? Yes. Can we practice LTE? Maybe not exactly but we can practice way too much pedal in One Direction. Can we practice Hydraulics off? Yes. Can we practice Vortex ring state recovery? Absolutely. Can we practice getting lost on a cross-country and then finding our directions again? Yes. Can we practice bad radio communication? Well that one is practiced automatically just by making so many mistakes communicating. Can we practice recovering from retreating blade stall? No absolutely not. The other reason I can think of why it freaks me out so much is the scenario it involves you being in. It's not just critical blade stall. It's not just pushover. It's not just gyroscopic precession and a lack of control. It's not just being overweight and the disc can't handle the load. It's not just a lack of control of the helicopter. It's not just instruments telling you everything is fine and obviously the helicopter is not. It's not just an uncontrollable vibration in the helicopter. Now where is with most issues you can somewhat some of the issues simply that "this is the issue" and to recover from the issue you "mostly do this and a little of this to recover." To me retreating blade stall is "first this happens and then it gets worse and then this happens and then it gets worse and then this happens and then it gets worse and then this happens and finally what could happen is who knows maybe the helicopter flips over and you fall out of the sky or maybe you blade stall and follow the sky or maybe you lose control and the helicopter shakes apart or maybe you inadvertently pull back too hard on the cyclic and chop the tail or maybe you encounter a mast bumping issue to recover from it you clearly want to reduce your speed but you don't want to do it too quickly you want to lower the collective and then go aft cyclic but nice and slowly nice and slowly nice and slowly nice and slowly just reduce the speed reduce the angle of attack." It sounds simple enough but we obviously can't go practice it and to me it makes auto rotations seem easy. It's just a number of things that go wrong and the main thing is obviously you're pushing way too fast and the rotor cannot handle even lift distribution anymore the advancing blade and the retreating blade and the advancing are and retreating are are not coordinating and one side of the helicopter is getting left in the other isn't and before you know it everything is just going bad first this happens and then this and then this and then this and then before you know it to recover you got a very slowly slowly slowly do this otherwise this is going to happen and this and this and this and this and this. To me this is the worst nightmare scenario. To me. I don't know about other Pilots. I can't say everyone has their own thing that really bothers them. And by no means am I trying to say those other things would not bother me. No emergency scenario is something you really want to go through whatsoever if you can try to avoid it whatsoever. But definitely retreating blade stalls one of those things that keeps me up at night that I just think constantly "wow I wish I wasn't even something that could go wrong." Additionally I feel like all your intuition would tell you to do the opposite in retreating blade stall. I feel like whenever you're having a problem with the helicopter the one thing you want to do is either get forward motion or increase the RPMs or both. The engine goes out and you're doing an auto rotation try and get that kinetic energy going to try and get those RPMs trying to get that forward speed don't overdo it but make sure you have that power. Really high density altitude? Try and make up for it with power with forward speed and RPMs. To me retreating blade stall is like that one scenario where all the things that you would intuitively do to get out of a stall are just going to make you still even more. Okay yeah you can say the same thing about Vortex ring state. You can say the same thing about getting too much of a Glide or not enough of a Glide or getting critical blade stall in an auto rotation where you added too much RPM you had too much forward speed you lost too much RPM you lost too much forward speed. Okay you're in Vortex ring state and instead of adding power you want to reduce the angle of attack and reduce the power the more power you add the worst it is going to get. But once again I feel like those things are things you go in practice you go and practice those things and you realize from experience that in this situation you want to do the opposite you don't want to add too much speed you don't want to add too much power you don't want to add too many RPMs you want to oppose that intuition and create an opposite intuition did in this situation you just need a certain amount of RPMs and a certain amount of power in a certain amount of forward speed and you can recover from the problem. To me though retreating blade stall is like every bad thing that could happen the helicopters stalling the helicopters flipping over the helicopters potentially shaking apart the controls are not going in the direction you want them to because you cannot compensate for gyroscopic precession with a pitch horn anymore it's like everything with the helicopter is just messing up backwards. I suppose the scenario to recover a simple enough kind of like Vortex ring State you just lower the collective reduce that angle of attack and then you can go after cycling instead of forward in Vortex ring state. But it's like aside from the fact that the helicopter controls aren't doing what you want them to do I feel like retreating blade stall creates a situation where the helicopters also about to shake apart or something as though you've created ground resonance. It's just an unexplainable nightmare to me and of course if I watch my density altitude and I watch my speed and don't over weigh the helicopter then I'll never have to worry about it. But wow is that scary or what? The thing could just totally tip over upside down before you nose down to the ground uncontrollably as well as maybe many other problems. We must remember what creates lift with a helicopter Bernoulli's principle and even lift distribution. We must remember why dissymetry of lift is something the rotor system has to compensate for whether it's with a fully rigid or semi rigid or fully articulated rotor system. We have to remember the teetering hinges allow the blades to Teeter allowing even lift distribution we must remember the coning hinges allow the blades to Cone independently of each other allowing the blades to operate and continue to create lift while changing the disc directions with the cyclic and the pitch angle with the collective without worrying that the coning will be either be excessive and the blades will not be able to properly produce lift or that the blades will not be able to cone whatsoever and handle the disc loading the weight of the helicopter whatsoever. I'm sorry if I got any of that explanation backwards where it's more of a vice versa thing. But you know what I'm saying. Retreating blade stall to me challenges all of the reactions of pilot would have of how to recover from a situation and at the same time challenges all of the reactions of pilot would have where practicing the recovery is something that you can just never do. I guess just remember your VNE remember the weight remember the density altitude you're working with for the day and practice the feeling that if you think you're going too fast for one reason or the other try and slow down but first lower the collective and reduce that angle of attack before going after cyclic. And just pray something you're never going to really have to recover from it because you're never going to get into it if you're smart enough. And try not to have nightmares about it like I do 😢 edit: also increasing rotor RPM with the governor does not seem intuitive along with lowering the collective and going aft cyclic

Why would the nose of the helicopter pitch upward ?

Is that flight footage in Alaska? Looks familiar! Also, great videos!

What's the relation between the angle of attack. And collective angle I didn't understand ?

I thought it was a slight roll to the right, mainly nose up, but also a bit to the right due to gyroscopic precession acting 90 degrees later, thus to the right. Anybody heard this before?

An excellent video but can you make your printing larger for those of us who have older eyes.

Hey, Jacob, Out of curiousity, Why dont you mention the blade flapping high on the advancing side and low on the retreating side??? This is was a pretty critical piece of my DoL lessons and yet its simply not mentioned here.

During low rpm , as long as you don’t pull up too much collective , it won’t create retreating blade stall .. thanks 🚁👌

So, you're saying I SHOULDN'T exceed the velocity never exceed?

Why turn right increase RPM.

Thank you. I say this is what happened to the kobe helo crash.

After deciding to switch to helicopters I also purchased the sportys helicopter add on videos and they are a complete waste of time in comparison to these