2017 Going out with a bang.....Flat Turns

[Dan Thomas]

So, we all agree that a "flat turn" has no utility in real flying, right? It offers no advantage over a normal, coordinated banked turn.

You are citing the SS as noteworthy because, if a pilot performs this maneuver at low speed (on purpose or by mistake), the results are less likely to be disastrous than in some other airplanes? Is that what all these threads have been about? Is this really a significant measure of merit for an airplane?

If we have to build idiot-proof airplanes so that we don't have to learn to fly, we're lost. Cars have been getting more and more idiot-proofing gizmos, and now the computers want to take over altogether and keep us from taking control. The autonomous car. Sounds good, except that it removes a certain satisfaction and liberty from your life in the name of safety. And the stuff that shows up in cars soon shows up in airplanes, and you will one day no longer be allowed to fly yourself around. Just sit there and tell the thing where you want to go, and it might obey you or it might say that it will take you somewhere else--or nowhere at all--because it has determined what's best for you.

If we build idiot-proof devices, society just comes up with better idiots. A stall/spin-proof airplane can still be flown VFR into IMC where control is lost and it crashes. An autopilot can be connected to the GPS so the airplane is flown safely through IMC, until the pilot runs out of fuel. So we connect the fuel gauges to the computer so the airplane won't start for a programmed cross-country if the tanks don't have enough fuel. We fill the tanks and take off, and mishandle the airplane on landing in a crosswind and wreck it. So the autopilot is upgraded to an autoland unit so we don't need to do the landing, either. Oh, and anti-skid brakes for the slippery runways, and a ballistic parachute just in case. At this point, the airplane--a 172--has an empty weight that has increased from 1450 to 1850 and is now a single-place, full-fuel airplane that costs $2.3 million. See where it leads? Do you want to learn to actually fly safely and affordably, or not fly at all?

 

[pictsidhe]

The Icon is a 'safe' plane, being stall and spin proof. Look at the attrition rate, though. Volvos are also touted as being very safe, but have a very high accident rate... I don't know about Storch accidents, but emulating promo stunts frequently goes badly wrong when amateurs try it.

 

[flyboy2160]

...It simply can't be disputed that the Slepcev Storch CAN perform these manuevers because there are several videos demonstrating those things....
View attachment 68345

What are the links to these videos?

 

[Topaz]

Moderator Note: This really isn't an aircraft design topic, it's a flying technique topic. I've moved the thread to Rules and Regulations / Flight Safety / Better Pilots from Aircraft Design.... Remember, the latter topic is not a catch-all.

 

[Winginit]

If we have to build idiot-proof airplanes so that we don't have to learn to fly, we're lost. If we build idiot-proof devices, society just comes up with better idiots.

Dan, we have all heard and probably used that oft cited cliche, but this is a serious topic and personal bias shouldn't cloud peoples judgement. Many things are incorporated into every design to make it safer. Lots of things can be upgraded without ruining the aircraft or overburdening a design. You mention anti-lock brakes. Should development have stopped at drum brakes, or was the technological advancement to discs acceptable ?

If you look at the historical development of the airplane you will find there has always been a quest to build safer airplanes. I don't think we have yet reached the point where any further development or adaption has become unnecessary.Pilots are still dying. You can trivialize the use of further technological development, but the simple fact that people like yourself can take wing and fly rides on the backs of many pilots who died because of a lack of technology. Should everyone have continued on at that level of technology and just considered dying an acceptable alternative to technological advancement? Should the wings the Wright brothers developed have signaled the end of wing development because people enjoyed the challenges presented by using them ? Your Jodel is the product of not only designers pushing previous technology ahead , but the result of the deaths and accident investigations of pilots using less technologically evolved airplanes.All thru aviation history, idiot proofing has been a part of evolution. You should also remember that the slatted wing technology was developed back in the 1930-40 era, so its hardly new technology. You can characterize it as "idiot proofing", but the truth is that very foolish to reject things which can make flying safer for you and your family. That being said, I think that there are many times when something may be slightly better than what is currently used on ones airplane, but isn't particularly needed. Its not always cut and dried that that something is always a better choice. Technology can be different, but not necessarily better. Look at aviation batteries, do you like the advancments being made there? Do you have a cell phone in your pocket that wasn't there when you learned to fly ? Do you like your big flat screen color TV better than the black and white Motorolas of the 50s ? Yep, we are all guilty of enjoying technological advancements, and each of us has the right to decide which airplanes have the technology level that we feel safe with. There is no logical reason to criticize people for making different choices than you do. Personally, I still have a flip phone and don't text, but the choice of other people to get the latest phones doesn't make them idiots. An awful lot of them really get some benefits from using them, so I say "good for them". You talk about being a flight instructor. Didn't you try to train your students in a manner that eliminated possible mistakes.....ergo an idiot proof regime for them to follow. Idiot proofing is not always a bad thing, because we have all had our moments.

And Yes, I still get pissed when my SUV automatically locks its doors at the wrong time............

 

[stuart fields]

If you find that flat turns at low airspeeds are important, I suggest you look into helicopters. Mine seems to be able to do them at just about any reasonable speed. I can also cruise at speeds higher than the published Storch speeds. Probably can't carry the loads, but performance in turbulence is better than any fixed wing I've flown.

 

[Turd Ferguson]

Many things are incorporated into every design to make it safer. Lots of things can be upgraded without ruining the aircraft or overburdening a design. You mention anti-lock brakes. Should development have stopped at drum brakes, or was the technological advancement to discs acceptable ?

I think that is the point several have made, the Storch offers zero in technological advancement. In fact, the technology used is from the 1930's. This is a case of foregoing disk brakes in order to continue using drum brakes, e.g. fixed slats are used instead of the more technically advanced retractable slats that don't penalize cruise performance.

personal bias shouldn't cloud peoples judgement

Yup!



Edit: I just saw a news blurb that 2017 was the safest year for air travel in history. The planes used in air travel do not make skidding turns in the pattern, in fact they usually have very nasty stall behavior. How can such a dangerous machine produce the best safety record in history?

 

[Winginit]

I decided to add the old Helio factory video just to show/remind people what a properly optimized slatted airplane is capable of. You can watch the whole video, but pay particular attention at the 2:50 and 3:20 marks of the video. Look at the controllability of this airplane, and its much larger and heavier than a homebuilt. Exceptional control ! Yet it uses a pair of wings, a fuselage, and a tail just like most other airplanes. What this should tell everyone is that the technology is available that allows exceptional control if anyone wishes to persue it. The initial goal during conception of the Helio was a "stall-proof/spin-proof everymans safety-plane". Thats what the industry set out to build using Handley-Page and Storch innovations along with their own ideas. The airplane is Legendary.
https://www.youtube.com/watch?v=QkiNYjOTT_s

Turd Ferguson Fortunately, the standard FAA traffic pattern does not require maximum performance maneuvering to arrive on final approach in landing configuration so the plane that can make the tightest turns has no material advantage over other planes in the pattern, i.e. no safer.

Not all landings are made at large airfields. In the following video, a landing is made at a somewhat difficult offroad site that requires a lot of concentration. Had an airplane been used that was optimized for the backwoods, the approach would have been much slower allowing a pilot more time to make any needed adjustment, and the shorter roll out due to lower speeds would give more room for error. This landing was successful, but you can hear the relief in the pilots voice. https://www.youtube.com/watch?v=HZwcRPcmnpY The thing you are not considering with the airport landing is that the advantage is not directed toward making a tighter turn in the pattern, but the ability to correct overshooting final or being blown off the centerline while on final. A more forgiving airplane may prevent a wing drop while attempting to correct. Therefore it should be safer.

Turd Ferguson The FAA says factors that contribute to loss of control "may include: poor judgment/aeronautical decision making, failure to recognize an aerodynamic stall or spin and execute corrective action, intentional regulatory non-compliance, low pilot time in aircraft make and model, lack of piloting ability, failure to maintain airspeed, failure to follow procedure, pilot inexperience and proficiency, or the use of over-the-counter drugs that impact pilot performance." all of those sound like pilot issues, not plane issues. They purposely stop short of blaming specific airplane types cause we all know pilots can crash even the safest airplanes built.

As you say, They are pilot issues. The idea is to equip a pilot with the best tool (airplane) to assist him....and provide protection when he does screw up.

Turd Ferguson;414491]I think that is the point several have made, the Storch offers zero in technological advancement. In fact, the technology used is from the 1930's. This is a case of foregoing disk brakes in order to continue using drum brakes, e.g. fixed slats are used instead of the more technically advanced retractable slats that don't penalize cruise performance.

Correct, it is not a current technological advancement and I haven't stated that it was. The idea of the floating slat also is not new technology, so had the Storch incorporated floating slats you could still make the same statement. The Slepcev is supposed to be a replica of a World War 2 airplane, not a new technological marvel. It is also a very safe airplane to fly even though/and because it uses that dated technology. In actual fact, the original Fiesler Storch was tested with floating slats and it was determined that the benefit (at that time/for that plane) was minimal given the mission of the plane. Fast forward and the Helio began using floating slats and is a proven airplane that still commands high prices. They could fly pretty fast, haul passengers or loads, and still land in parking lots. The factory video of Helios performing is awesome. Now there is a resurgence among pilots using various means of attaching movable slats. The Pegazair uses tubes which move in and out like the Helio. The Just STOL planes (new tech ?) have a hinged slat that moves outward and sideways....much simpler. The Mackey SQ2 uses a pivoting slat, and Dakota Cubs uses a slot. Move on up to the big boys with passenger jet airliners and you see all sorts of innovation...of this old technology. Most homebuilt airplanes do not incorporate slats because its more difficult to build, takes longer, and increases costs in a very competitive situation.....not because it isn't an improvement.

Turd Ferguson Edit: I just saw a news blurb that 2017 was the safest year for air travel in history. The planes used in air travel do not make skidding turns in the pattern, in fact they usually have very nasty stall behavior. How can such a dangerous machine produce the best safety record in history?

So, should we be satisfied with that or continue to seek improvement ?

Notice in the next video that its a beautiful clear day at a large grass runway and yet two airplanes managed to wrap themselves up and a child died. While slatted wings would not have prevented this tragedy, technology does exist that would have prevented it. https://www.youtube.com/watch?v=nW1ita8gZpk

In the last video, they offer suggestions on how to fly and land in the backwoods. Notice that they always try to enter straight in with wings level, and point out that while typical spam cans can land, the dedicated off airport designs are safer.
https://www.youtube.com/watch?v=J4NnmbbSizQ&t=239s (pay particular attention to what is said at the 6:35 point

 

[12notes]

So, should we be satisfied with that or continue to seek improvement ?

We should continue to seek improvement. Which is exactly why we do not do flat turns in pretty much any circumstance, nor teach them, as the banked turn was the improvement sought after. Returning to a repeatedly and consistently proven to be inferior method of turning is pointless. There is no advantage to the Storch compared to nearly every other plane with a low stall speed. The only thing that the ability to do a flat turn proves is margin over stall speed, nothing else. Lower stall speeds are great, but not at the cost of nearly every other mission requirement. Those of us who wanted a super low stall speed would've built or bought a plane with one. Those who value other requirements more build and buy otherwise.

 

[BBerson]

I think any airplane that can do a tight flat turn has too much rudder area and also too much rudder travel for normal use. And with this excess rudder control is easily spun at stall.
So by definition is not idiot proof and should not be owned by other than professional stunt pilots.

 

[BJC]

When you think that you have designed something that is idiot proof, you soon will learn that you have underestimated the ingenuity of idiots.


BJC

 

[Dan Thomas]

The thing you are not considering with the airport landing is that the advantage is not directed toward making a tighter turn in the pattern, but the ability to correct overshooting final or being blown off the centerline while on final. A more forgiving airplane may prevent a wing drop while attempting to correct. Therefore it should be safer.

As you say, They are pilot issues. The idea is to equip a pilot with the best tool (airplane) to assist him....and provide protection when he does screw up.

Most accidents are pilot error, and just about all pilot error is due to (A) poor training, or (B) a bad attitude. Bad attitudes include the Five Hazardous Attitudes, established by years of research and experience in the industry. Anti-Authority. Machoism. Impulsivity. Invulnerability. Resignation. All of us have at least a bit of each, and the most dangerous pilots have a big bunch of at least one of them. Designing a safe airplane will make no difference whatever to these pilots. They will find ways to hurt or kill themselves and their passengers. There are numerous websites detailing this stuff, complete with tests you can take to see where you fit in the matrix. In some groundschool classes I've heard students dispute the results of their test: "That's not me!" And the rest of the students say, "Yes, it is!" You see, if we're not open to training, criticism and correction, we won't be safe and knowledgeable pilots. Bad pilots lead to more and more regulations and laws that cost all of us a lot of money, and governments will keep on wrapping chains around us in an attempt to control stupidity. When autonomous airplanes are developed, they'll force us to junk our old airplanes and buy the new, safe airplanes. Homebuilding will be outlawed.

The whole idea of skidding a turn onto final to avoid banking is absolutely unscientific and has been shown to frequently cause stalls and spins in ALL types of fixed-wing airplanes, including STOL airplanes with slats. Any instructor who advocated this would have his certificate revoked. A banked turn is not only safer, but actually puts the airplane where you want it a lot sooner. There is no advantage to skidding. None at all. People who are afraid of banking simply aren't studying the numbers: a 30-degree banked turn, the recommended max in the circuit, raises the level-flight load factor of 1.0 to 1.154, and the stall speed rises by the square root of that, or 1.074. That means that an airplane that stalls at 40 knots, say, will stall at 42.96 knots in that 30° bank. If we're doing the typical 1.3Vso on approach, we're at 52 knots, still far above that 43-knot stall. Skidding the airplane lowers the inside aileron, canting the chordline upward and brings the outer wing area much closer to its stall angle, and nasty things can happen well above 43 knots. Plainly, it's dumb to skid in the circuit. Period.

Good training is important, and that includes studying the stuff you're supposed to study until you understand it. And a good instructor will then take you out and demonstrate, in very stark and unforgettable ways, what the books are talking about. You gain understanding that appears to be in short supply these days, since so many accidents are so completely avoidable, and most of them wouldn't have been prevented by more technology. Besides that, the low-speed stall-spin in the circuit doesn't kill as many people as flying VFR into IMC does, or running out of fuel, or buzzing and pulling up and getting an accelerated stall, or flying low and colliding with wires or trees or whatever, or performing unauthorized aerobatics, or suffering engine failure due to really basic stuff like carb ice. There are many ways to do it, and skidding a low-speed turn is only one of them.

There is no substitute for flight training. I often found hardened attitudes changing within the first few hours when the student began to discover that things were not at all what he thought they were. Preconceptions tend to change real quick. Those here than haven't flown need to go out and get some intro to it. If nothing else, it will get you studying the right stuff, the established textbooks, not magazine articles. There are many misconceptions out there.

 

[BBerson]

If a tailwind requires a bit more turn rate than the recommended 30° bank, then more bank can be added to say 45°. But do ease the stick forward a bit to keep safely above stall angle (if high enough, if not then add power and go around)
The chart g load factor data is for level flight. A 45° bank in descent to land can be less than 1.4g if the stick is forward. The stick instantly controls g load.

The 45° bank is much preferred to skidding, in my opinion. Skidding is with bottom rudder and that points the nose downward so the pilot naturally pulls back on the stick and stalls. Don't do it.
Re-read "Stick And Rudder" to review how to properly turn at least once per year.

 

[pictsidhe]

Slats don't prevent stalls. They merely increase the maximum angle of attack and Cl. Many airliners and fighters have them.

I've always thought that the Hawker Siddeley Harrier had the ultimate low speed control. Should we be attempting to build something like that? they still managed to crash, though. Long list

How about we move on to the benefits of aircraft such as the Su-27 that can perform Pugachev's cobra? Now there's some impressive flying. I'm waiting for the aircraft that can do a treble back flip and then recover. That will be sometime after the one that does a single back flip.

 

[Dan Thomas]

If a tailwind requires a bit more turn rate than the recommended 30° bank, then more bank can be added to say 45°. But do ease the stick forward a bit to keep safely above stall angle (if high enough, if not then add power and go around)
The chart g load factor data is for level flight. A 45° bank in descent to land can be less than 1.4g if the stick is forward. The stick instantly controls g load.

Here's the thing with lowering the nose: it reduces the load factor only as long as the descent is accelerating. In any descent, whether in straight or turning flight, if the rate of descent is steady, the load factor is essentially the same as if it was not descending. The same applies to a climb. The g load changes only while the flight path is curving. That's why a level turn has a higher load factor. That's why pushing forward momentarily reduces the load factor and you feel light in your seat, or pulling back and you momentarily get heavier. They train astronauts for zero-g by climbing the airplane and then pushing forward and holding the controls to achieve zero G; the airplane curves over the top and starts descending at an ever-increasing rate. They can carry that only so far, of course. Or they could dive straight down at ever-increasing speed.

In a base-to-final turn, we can't rely on lowering load factor "because it's descending." Doesn't work, unless the descent is quite steep and weight is acting less through the vertical axis and more through the longitudinal. https://www.theairlinepilots.com/forum/viewtopic.php?p=792

 

[BBerson]

Yes, the reduction in g load is momentary. But with the stick forward the speed will also increase to compensate. It might only take about 2 seconds at 45° bank and then back to 30° or 0° if done turning and then ease the stick back again to normal approach glide speed. It's second nature to a glider pilot that does the stick forward movement routine perhaps 100 times in a 30 minute thermal. Glider pilots routinely bank at 60° and get real good at catching the stall burble with a quick stick jab forward.
Most pilots don't get this practice.
I don't think any student pilot manual I ever seen had stated that the stick controls the momentary g load.

 

[Turd Ferguson]

In all the bush flying videos I never see any pilots making skidding turns which is in line with the overwhelming consensus that coordinated turns are best especially when maneuvering for landing.

Bush flying is a niche (a small one at that), the equipment used and many techniques do not transfer to mainstream flying. IOW's it's not going to make mainstream flying any safer.

There is not a technology solution to every problem. For many years the company Flight Safety International used the slogan 'The best safety device in any airplane is a well trained pilot' and they still use a variation of that statement. Using that I can tell you how to get maximum safety benefit for each dollar invested but it's not what most people want to hear.

 

[Dan Thomas]

In all the bush flying videos I never see any pilots making skidding turns which is in line with the overwhelming consensus that coordinated turns are best especially when maneuvering for landing.

Bush flying is a niche (a small one at that), the equipment used and many techniques do not transfer to mainstream flying. IOW's it's not going to make mainstream flying any safer.

There is not a technology solution to every problem. For many years the company Flight Safety International used the slogan 'The best safety device in any airplane is a well trained pilot' and they still use a variation of that statement. Using that I can tell you how to get maximum safety benefit for each dollar invested but it's not what most people want to hear.

That right there. It ain't what they want to hear. They'd rather spend vast sums on idiot-proofing that doesn't work rather than study and practice so that ignorant mistakes simply don't happen. I don't get it.

 

[Winginit]

That right there. It ain't what they want to hear. They'd rather spend vast sums on idiot-proofing that doesn't work rather than study and practice so that ignorant mistakes simply don't happen. I don't get it.

Dan, I usually give you credit for thoughtful replies even if I disagree with you, but that comment is totally baseless. Its overly broad and mistated information like this that ruins useful internet dialogues. First tell us what these "vast sums of money" are that builders and designers are spending. Second, no matter how much training and practice pilots have, they are human beings and they will always make mistakes....always have and always will. You are the same person who thought it acceptable for people to die because you feel they should have taken more training on "carb icing" procedures and recognition. In the example discussed on a previous thread the pilot who died in the icing incident was a professional flight instructor. How much more training did he need ? He was teaching a student at the time. Not all flight instructors make the right decision, neither do all pilots, definitely not all students. You throw the term "idiot proofing" out there because its one of those things that we all have distain for when things reach the point of overkill and overeach....but you should be careful about what you wish for and when you apply that terminology to something.

If someone could design an airplane that no matter what happened it would never stall and no one would ever lose their life because of a landing stall....would that be a good thing or would you protest that innovation?

If someone could redesign carbureted systems so that an inexpensive modification prevented anyone from ever having an engine out because of icing....would that be a good thing or would you protest that too?

Why are you so adamantly against anything that simply improves the margins of safety when you know it is an absolute certainty that pilots will continue to make mistakes, fatal mistakes? Tell me that you or anyone else out there has a plan that is an absolute certainty to prevent human error. You don't. You can't. And you never will be able to do that. You need to quit showing distain for things that may save a life someday just because you don't personally like them. They are a supplement to training, not a detriment. No one is suggesting that pilots be taught to do flat turns as part of their training regimen, or to deviate in any way from proper and accepted landing procedures. All thats being proffered here is that certain design features may help a pilot thru a lapse in judgement.

 

[Rockiedog2]

I wonder if Eikminierro has ever flown a plane.