# Flying below at or below minimum airspeed, and Fixed wing vs. Rotorcraft Stalls

#### All_In

##### Gold Supporter
Here is the first rough draft of the new section I will add to the rotorcraft aerodynamics presentation. Please help me get this right!

I've tried to express in correctly as I understand it in the simplest term I know now. Please feel free to pick it a part. That how I test my opinions and the only thing I do better than believing what I know is changing once show the error of my ways.

==== Start ===
Flying at or below minimum airspeed, and Fixed wing vs. Rotorcraft Stalls

During a banked turn the lift on the aircraft must support the weight of the aircraft, as well as provide the necessary NEW component of horizontal force to cause centripetal acceleration. Consequently, the lift required in a banked turn is greater than that one required in straight, level flight is by increasing the angle of attack. The maneuver is usually complemented by an increase in power, in order to maintain airspeed.

CLT and statically stable aircraft:
In all airfoil aircraft, not lighter than air aircraft, you must bring the nose up. With aircraft that are Center Line Trust and statically stable with respect to G-load it's necessary to use aft stick pressure to execute a level, banked turn at constant airspeed.

FW or rotorcraft both apply the laws of flight physics EXACTLY the same; All airfoil aircraft you must raise the nose, change pitch, of the aircraft in a banked turn, FW you raise the nose just a little even in a shallow turn.

Why because any moving vehicle or aircraft making a turn, it is necessary for the forces acting on the aircraft to add up to a NEW net inward force if you look at the picture there is a new horizontal force (centripetal acceleration) that is stealing some of your lift in a banked turn, examine the picture and see the yellow arrow. The more you bank the more it steals.
Same in a car this force is what makes you slide off the road in a turn.

The more weight you are carrying in a banked turn the more airspeed you need to counter the centripetal acceleration. Near stall airspeed, you REALLY need to learn what airspeed your aircraft needs to carry max gross weight thru any bank angle you may fly. Especially when low to the ground approaches to the airport when turning final. This is where many accidents occur and or turning low to the ground at slow airspeed on down wind turns.

Realize this will be at a much different and slower airspeed in a gyro than a FW for them to even be compared and only then once flying to slow and both pilots are in trouble.

The biggest differences between FW and rotorwing is the DRAG, the minimum safe airspeed difference is extreme, and in gyroplanes rotorblade ground taxi management and pre-rotation take-off procedures.
The drag you can see when you pull power noticing the GUIDE RATIO compared to FW. Gyro 4 to 1, FW 10 to 1 at least; that’s 25% of the lift of a fixed wing. Once in trouble you are going to have to add 4 times as much power OR 4 times as much changing the pitch to counter the exact SAME centripetal acceleration in rotorcraft however, rotorcraft flies often 4 time slower so it's harder to get in trouble compared to FW in this regard too and faster time to recover at a much slower safe airspeed in a gyro, although FW'er will notice a LAG to regain airspeed compared to FW on your first behind the power curve landing in a gyroplane. You should not be flying 20 knots an hour in a gyroplane or 45 to 60 knots in most small FW's (just an example).

Now raising the nose even a little is going to increase your angle of attack increasing DRAG so a turn at LOW AIR SPEEDS will always require more airspeed in any turn in both FW and Rotorwing.

This means it 4 times easier once you are in trouble in a gyroplane and 4 times harder to get out of trouble AT LOW AIR SPEEDS sort of 4 times the lag time compared to FW. JUST maintain the correct airspeed or do not turn = land straight ahead!
Rotorcraft also do not stall the same and sort of mush into the ground with less server impact compared to FW sort of like having too small of parachute see stalls below.

High Trust Line HTL you may not pull back on the stick and is different than CLT:

In some HTL, statically unstable gyros, though, the fore-aft stick pressure feedback with changing G-loads is apt to be reversed. In these craft, it's necessary to add FORWARD pressure to avoid mushing out of a turn, once you've settled into your bank. Newbies in Bensens used to mush out of turns all the time.

The need for forward stick to hold speed in a turn is one quick way to diagnose uncompensated HTL in a gyro. It's not foolproof; much depends on the trim spring rate, head offset, spring setup and a bunch of other variables.
The fact that a slowed-up gyro falls out of a turn in a mush while a slowed-up FW stalls and goes straight in is apt to be cold comfort to the aircraft's occupants. The pilots of both craft must go against every human instinct and get the stick forward to regain airspeed -- and tolerate the temporarily-increased rate of fall that this input causes. It takes guts -- and it may not work if the ground catches you before you do regain that speed.

Stall and FW vs Rotorcraft:

If you are flying at MINIMUM airspeed with a HEADWIND and turn downwind with a wind speed grater than 0 = What do you think is going to happen if you do not increase your airspeed by the exact or greater amount than minimum airspeed needed to counter centripetal acceleration to maintain altitude? You start and uncontrollable descend, and or stall and spin in a FW, until you either gain airspeed or hit the ground.

The gyro's advantage over the FW is not that it won't fall out of a turn in the absence of airspeed ('cause it will). Rather, the gyro mushes instead of freefalling, as the FW does. The gyro pilot still has full cyclic control; he just can't immediately arrest the descent. Moreover, the gyro mushes downward slower than a FW plane falls in stall -- so if worse comes to worst, the gyro will hit the ground at a speed and attitude that may be survivable.

The most important difference, though, IMHO, is that gyros don't lose lift on one side of their "wing" while maintaining it on the other -- IOW, they don't spin. FW planes, to various degrees, are spirally unstable and tent to tighten a banked turn, and to "lock in" to a spin. You can't just "high stick" your way out of a spin. The gyro has no tendency to tighten in the first place, and you can always "lift a wing" in a gyro by simply high-sticking. You don't have to "trick" the aircraft into leveling out with the use of rudder, as in a spinning FW.

The most vicious part of a stall-spin is the spin. We gyro folk are free of that monster -- though we still are bound by the need for airspeed.

It’s important to know that FW and rotorcraft stall differently and at much different airspeeds but the solution is exactly the same for both!
Airspeed... either more power or point the nose down to gain airspeed.
There are no other options!

However, over coming human nature to point at the ground when so close and looking right at it can only be over come with training at altitude so it's so automatic you don't even notice the ground only the airspeed indicator as you hit the ground.

JUST WATCH YOUR AIRSPEED INDICATOR and KNOW how much power you may need to add in a turn and if you need to pull your stick back or forward and this will not happen in either a FW or rotorwing aircraft!

Uncontrolled descents and stalls CANNOT happen with the correct airspeed no matter what the bank angle and the wind speed or direction with in reason.

===END---
A little help Doug?

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#### Panzl7

##### Gjunkie
Great article John. I am a newbie, met you at Mentone last year, hoping to be able to fly safely and become proficient like most of you. I was able to understand it easier by comparing it to FW. Learned something new, thank you!

#### kolibri282

##### Active Member
The more weight you are carrying in a banked turn the more airspeed
This is true, John, if your airplane is close to stalling, otherwise you could increase the angle of attack to get the extra lift needed. If I did get you right in that you imply an aircraft close to stall it might be helpful to state this as one initial condition. I think it is generally a great idea to open a thread that deals with one particular maneuver and thoroughly investigate what it takes to complete this maneuver under various circumstances. It takes guts to offer ones ideas for discussion and I do hope that many of the other experienced members of the forum will chime in and make this a good read for us newbies.

Happy New Year, John and may your worries become smaller every day!

Yours, Juergen

PS: ...and yes, it is helpful to add redundant information for dummies...;-)

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#### All_In

##### Gold Supporter
Great article John. I am a newbie, met you at Mentone last year, hoping to be able to fly safely and become proficient like most of you. I was able to understand it easier by comparing it to FW. Learned something new, thank you!
Thank you it will be change to clarify and of course for any errors found I want corrected.
It's help me too, as I must write it. It's clarifies my understanding too.

#### All_In

##### Gold Supporter
Yes and tried to convey when in trouble for both at different airspeed with the title Flying at or below minimum airspeed, and Fixed wing vs. Rotorcraft Stalls.

But will add near a stall.
Thank you and Happy New Year to you and thanks for all your posts they have helped me learn so much!

PS:
The only way it to test my opinions are to put them out there for CHANGE! Also long as I learn the correct answer too I do not care I was wrong only learning the correct answer matters and passing that along until someone points out a flaw and change again. I pride myself on how quickly I can change once I understand why, or how it works.

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#### All_In

##### Gold Supporter
I've made a few changes I noticed comparing airspeed between FW and gyroplanes.

The biggest differences between FW and rotorwing is the DRAG, the minimum safe airspeed difference is extreme, and in gyroplanes rotorblade ground taxi management and pre-rotation take-off procedures.
The drag you can see when you pull power noticing the GUIDE RATIO compared to FW. Gyro 4 to 1, FW 10 to 1 at least; that’s 25% of the lift of a fixed wing. Once in trouble you are going to have to add 4 times as much power OR 4 times as much changing the pitch to counter the exact SAME centripetal acceleration in rotorcraft however, rotorcraft flies often 4 time slower so it's harder to get in trouble compared to FW in this regard too and faster time to recover at a much slower safe airspeed in a gyro, although FW'er will notice is a LAG compared to FW on your first behind the power curve landing in a gyroplane. You should not be flying 20 knots an hour in a gyroplane or 45 to 60 knots in most small FW's (just an example).

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#### Stan V

##### Active Member
John, you are making a lot of absolutes in your post, stating things like what can not happen. A tractor FW in a stall with a lot of power in, will hang on its prop (fly behind the pwr curve) where a pusher FW will stall at the same AoA with pwr in or not. The spin will only occur if you help the stall along with a little rudder. Recovery not only requires (nose down) airspeed but opposite rudder.

#### Gyro_Kai

##### Senior Member
Hello John,

a couple of things struck me:
If you are flying at MINIMUM airspeed with a HEADWIND and turn downwind with a wind speed grater than 0 = What do you think is going to happen if you do not increase your airspeed by the exact or greater amount than minimum airspeed needed to counter centripetal acceleration to maintain altitude? You start and uncontrollable descend, and or stall and spin in a FW, until you either gain airspeed or hit the ground.
You should include GROUND- every time you mention speed in the above sentence. If you fly constant airspeed circles in wind, you will fly happily in overlapping ellipse-spirals in the direction of the wind. Just watch your airspeed as you fly and you are alright. The only danger of the downwind turn is that pilots may use ground reference as speed indicator. That is fatal.
The gyro's advantage over the FW is not that it won't fall out of a turn in the absence of airspeed ('cause it will). Rather, the gyro mushes instead of freefalling, as the FW does. The gyro pilot still has full cyclic control; he just can't immediately arrest the descent.
You have a different concept of stall. The German word for stall is very technical, „Strömungsabriss“ and means, airstream-disconnect. The air is not flowing over the wing any more, providing lift, but disconnects and becomes turbulent. The Aircraft becomes a simple cross and falls out of the sky like a stone, until the airstream re-attaches.

The gyro-rotor-wings never ever stall fully if the plane is too slow. They re-adjust their RPMs automatically and you sink with full control vertically. Quite different to a fixed wing. It is not a good way of landing, but you still can recover easily out of this, especially, if the engine is still running.

Kai.

#### Vance

##### Gyroplane CFI
Here is the first rough draft of the new section I will add to the rotorcraft aerodynamics presentation. Please help me get this right!

I've tried to express in correctly as I understand it in the simplest term I know now. Please feel free to pick it a part. That how I test my opinions and the only thing I do better than believing what I know is changing once show the error of my ways.

==== Start ===
Flying at or below minimum airspeed, and Fixed wing vs. Rotorcraft Stalls

===END---
A little help Doug?
Beginning and ending with the first sentence in bold.

From the 2014 edition of the Federal Aviation Regulations:

“Rotorcraft means a heavier-than-air aircraft that depends principally for its support in flight on the lift generated by one or more rotors.”

“Gyroplane means a rotorcraft whose rotors, are not engine-driven, except for initial starting, but are made to rotate by the action of the air when the rotorcraft is moving; and whose means of propulsion, consisting usually of a conventional propellers, is independent of the rotor system.”

“Helicopter means a rotorcraft that for its horizontal motion depends principally on the engine driven rotors.”

In my opinion a gyroplane does not fly like a helicopter.

In my opinion a rotorcraft will not stall because of flying below the "minimum air speed" so there is no “fixed wing vs. rotorcraft stalls.”

In other words a gyroplane does not have a Vs.

I feel there is value in using the generally accepted terminology correctly.

I feel it is a mistake to compare things that are not comparable.

Regards, Vance

#### RotorTom

##### Member
H==== Start ===
Flying at or below minimum airspeed, and Fixed wing vs. Rotorcraft StallsDuring a banked turn the lift on the aircraft must support the weight of the aircraft, as well as provide the necessary NEW component of horizontal force to cause centripetal acceleration. Consequently, the lift required in a banked turn is greater than that one required in straight, level flight is by increasing the angle of attack. The maneuver is usually complemented by an increase in power, in order to maintain airspeed.
Let's just take this statement ... "the lift required in a banked turn is greater than that one required in straight, level flight" (and I hope the experienced among us will get the true gist of my disagreement ... which follows):

"MORE" lift is NOT required in a turn. It is the same amount of lift but the flight surfaces are less efficient due to their angles causing us to manipulate them to create the SAME amount of lift as before.

The "centrifugal" forces (being flung from center) and/or the centripetal forces (being drawn to center) of turns are counteracted with rudder forces (which technically increase or diminish lift on their surfaces) but I do not believe that is the lift you were referring to.

Again ... look at the essence of what you are saying.

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#### All_In

##### Gold Supporter
Thank Stavn V, Kai and Vance this was really helpful to me.

But seems I'm not qualified to write about this on this forum until after I have some unknown to me # of hours.

So Please close this thread unless someone with more time in gyroplanes will take it on so we can continue learning?

Thanks, it was fun while it lasted especially the talks about politics really enjoyed learning what other folks felt and knew.

#### TJMay

##### Gold Supporter
John,

That sounds a bit like "well, I'm taking my home plate and leaving."

Your enthusiasm and passion got a little out of control.

Don't go away; continue to ask questions but keep your remarks to facts that are within your level of knowledge.

Tommy

#### All_In

##### Gold Supporter
John,

That sounds a bit like "well, I'm taking my home plate and leaving."

Your enthusiasm and passion got a little out of control.

Don't go away; continue to ask questions but keep your remarks to facts that are within your level of knowledge.

Tommy
Sorry only way I know to keep many of my friends happy here.

I have so much on my plate if it's not helping others then I have no excuse spending the time to be here.
I do not really have the time for pleasure right now family and friends #1, exercise is #2, invention #3, work #4, helping others here and elsewhere #5, building a customers gyroplane and flight training #6, and self enjoyment reading this forum last place.

I'll be back once I've have flown the # of hours Vance feels is required for me to be able to ask for help with my opinions again. It will depend on when Vance will let me help others learn and I'll post my flight experiences if I'm allowed as a newbie gyroplane pilot.

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#### TJMay

##### Gold Supporter
Sorry only way I know to keep many of my friends happy here. I have so much on my plate if it's not helping others then I have no excuse spending the time to be here. I do not really have the time for pleasure right now family and friends #1, exercise is #2, invention #3, work #4, helping others here and elsewhere #5, building a customers gyroplane and flight training #6, and self enjoyment reading this forum last place. I'll be back once I've have flown the # of hours Vance feels is required for me to be able to ask for help with my opinions again. It will depend on when Vance will let me help others learn and I'll post my flight experiences if I'm allowed as a newbie gyroplane pilot.
Again, John, that sounds like if you don't like me, then "I'll take my home plate and go home."

While most of us respect and revere Vance, he doesn't have the power to place an hourly limit on when you can post and when you can't, unless you let him.

I don't believe any one of us want you to stop posting regardless of how many hours you have. Just post from your own personal experiences and knowledge, not conjecture.

Tommy

#### StanFoster

##### Active Member
John- Please continue to post your opinions. We all can learn from everyone here. None of us have all the answers...but most of us have some of the answers.

Stan

#### All_In

##### Gold Supporter
Again, John, that sounds like if you don't like me, then "I'll take my home plate and go home."

While most of us respect and revere Vance, he doesn't have the power to place an hourly limit on when you can post and when you can't, unless you let him.

I don't believe any one of us want you to stop posting regardless of how many hours you have. Just post from your own personal experiences and knowledge, not conjecture.

Tommy
Boy I do not know what to do to make everyone happy… When I ask for help”
From Vance:
“Please learn to fly a gyroplane before you give advice to others about how it is just like a fixed wing.

I feel it is important to not mislead people with fantasy.”

… and then this:
“In my opinion some of your conclusions about how a gyroplane flies are flawed John.

I am not comfortable letting incorrect information go unchallenged on this forum because I have often seen it become the new truth.

I have seen dangerous concepts become a debate based on incorrect information presented here.”
I sure do not wish to do that!

From another wise and good friend whose opinion I respect and have learned from was:
Get trained to fly a gyroplane, finish that gyro build, fly it. You seem very passionate about gyroplanes, get off the keyboard and go do it!
And… another brought up motives I would have never thought of in 100 years.

And from the woman I idolize:
“I would love to see you help yourself first by learning to fly a gyro and becoming expert at it and be one of the regular gyro types.”
Basically shut up and and go fly away from all of them? If it's helping no one what is the point!

So I’m, trying to honor their wishes and wait until I have whatever the # of hours needed to finish this so the home plate will come back once allowed and everyone is happy again.

This is when from my perspective; what I got back from Vance was very frustrating as he would only provide a vague response that my theory was flawed and I did not have enough time in type to post my opinions.

What I was asking was what parts were flawed the whole thing? This was all I was asking, the part Doug wrote I copied and pasted the part from others on the forum, the part that came from aerodynamic books and reports or was it how I strung it all together to make it more like an story and in order?
What line or sentence and how to correct it was how they use to respond and for over 20 pages now I was allowed to do so whit only 3 hours logged at that time… Now it's a problem for this one. Things have changed here!

Then Vance actually helps in this thread with specifics I could really use so that even confused me more! I added it to the page and all the others and will wait.

Really the last straw was when motives other than trying to help others who follow us. It's seems they think I have a self serving motive and that's just not me so I'm out of here to make those I respect happy. What else can I do?

I'm truly sorry I caused so much discontent.

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#### j bird

##### Gold Supporter
John, Home Boy, (Orinda), hang in there, sometimes a little rain must fall, seams like you've had a lot lately, keep a stiff upper lip, when things get rough, the tough get going.

#### kolibri282

##### Active Member
"MORE" lift is NOT required in a turn. It is the same amount of lift but the flight surfaces are less efficient due to their angles causing us to manipulate them to create the SAME amount of lift as before.
Lift is the force generated by the wings to support the aircraft in a certain flight attitude, this force is perpendicular to the oncoming air and a line that passes through the wing tips. If an aircraft flies at 300 km/h in a circle with a radius of 708 m the centrifugal acceleration is 9.81 m/s² which is the gravity of the earth or one g. This acceleration adds up to earth gravity which is still pointing downwards to a total force of square root of two times g (times mass of the aircraft). The wings generate the force in the opposite direction which has to have the same magnitude to assure a steady turn. For this lift force to lay exactly opposite the total acceleration force the aircraft has to fly at a bank angle of 45° and the total lift is 40% larger than in straight and level flight. The purpose of the control surfaces is to assure that the aircraft is flying at the attitude required for the wings to generate that force. By the way the extra lift required is the reason why you have to add power in a turn if you don't want to lose height.

Generally I think that in a discussion time spent flying an aircraft has no value in itself, it should be reflected in better arguments and a more clear sighted explanation of phenomena. Many discussions in this forum have been focused on helping all to better understand the subject of the discussion, this should remain the first and foremost goal of any argument

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#### Kevin_Richey

##### Yamaha gyro...Oregon, USA
All-In!

All-In!

John: I respect your enthusiam, drive, and friendliness to all.

It seems out of character for you to think you've been told to shut up and fly, as well as your thinking that everyone is jumping all over you.

Your knowledge of all things airplane and their flight is huge. Your gyro knowledge is still to grow quite a bit to match your fixed-wing expertise. Please don't go down the path that some do here in the past and think you have been ganged up on and that you are "outta here"!

I believe that most of those who have left this forum over the years in a huff, and also most of the few that have been banned from this forum have been because of their immaturity to interact well with the majority of forum members as well as the moderators and the owner of this forum.

You don't seem to fit that mold.

I am aware of the Wolverine forum and have visited ocasionally to attempt to learn from the rotorcraft knowledge there. While there is some of that there, such as Gabor's build, most of the comments are non-rotorcraft related, and some are negative comments directed towards this forum.

Unfortunately, one poster there thinks repeatedly posting three words ad naseum (two of which are consider impolite and extremely unpleasant expressions for most of civilized society) is something worthwhile for all to read.

Flying aircraft is such a thrill! Dont get bent out of shape because some of your friends suggest you get more gyro-flying experience and learn more about flying the poor-man's helicopter. You have many talents. Don't jump to conclusions that appear to me are incorrect about people telling you to shut up, or basically to go away and get a lot of gyro flying experience before you can post again.

You have so much going for you and also so much going on in your life. You are attempting to do a heck of a lot of innovative things to create a huge training center in California for gyros. It still amazes me that in the state of California doesn't have any active gyro CFI's that train in experimental gyros!

I believe Jon (Starks?) will train in either the Air & Space 18A or McCulloch J-2 certified gyros up around San Jose. But, for the population and economy of California, there should be a huge demand for it!

John: You've read my thoughts gyro-related. I'm going to add something else. I have relatives that are/were heavy, heavy smokers. They lived/live in the SF bay area.Virtually all my cousins there took up the nasty habit when they were young. Their parents were terrible examples and all but one of them became smokers.

Seven of them died from cancer and smoking-related diseases. Before those died, those had severe health issues. I truly believe smoking stresses the human body in many ways, even more than scientists can prove w/ research. My cousins left alive have all finally quit smoking. The last one was the most die-hard smoker and literally yelled at anyone of her family that tried to get her to kick the nasty habit. After she had lost her father, mother, and three brothers to lung cancer and emphisema (sp?), she came to her senses.

I also have observed several relatively-young co-workers who were heavy smokers in the past several years get diagnosed with major cancer growths, start aggressive treatments, and some then get struck down by strokes, and are gone shortly thereafter. Some older co-workers that were also heavy smokers battle cancer, think they have it beat, and then it roars back, cutting them down this time. The non-smoking co-workers don't seem to have nearly the severe health issues.

I can't prove that you have health problems because of your cigarette habit.

But the facts are there about the majority of smokers having other health issues and their health usually improves when they give up the tar and other chemicals that are burnt in each cancer-stick.

My wish is that you can join guys in our rotorcraft world that have quit and have been glad they did, like Dave Bacon, Mike Groshans, Paul Plack, Ben Souisa, Gilbert Sherperd (Bensen flyer from Oregon that comes to El Mirage), and others.

I believe you are a god-send to ignite the west coast into a gyro-mecca of training and flying. We need you to be in good health to finish your work!

If you are offended by what I have written here, so be it.

I will still respect you for all your good character traits and projects you want to accomplish. And, I will still think of you as a friend.

If you aren't offended, so much for the better.

I can't wait to see you flying solo in a gyroplane!
If you are excited about things now, when you solo, you probably will be bouncing off any wall you see, and never shut up about it!

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#### birdy

##### Newbie
"Basically shut up and and go fly away from all of them? If it's helping no one what is the point!"
Hava good feed of cement John, then come back swingin.
You should never expect to make everyone happy.

Wot your attemptn to do is VERY involved, and wot Vance n co are do,n is offering responcable criticism of your posts, not your aim.

Blanket explanations can be very dangerous.