Controllability vs Maneuverability?

[CC268]

The definitions in the PHAK are somewhat confusing to me. I understand controllability, but I am having a difficult time explaining maneuverability in laymans terms.

PHAK definitions:

Maneuverability—the quality of an aircraft that permits it to be maneuvered easily and to withstand the stresses imposed by maneuvers. It is governed by the aircraft’s weight, inertia, size and location of flight controls, structural strength, and powerplant. It too is an aircraft design characteristic.

Controllability—the capability of an aircraft to respond to the pilot’s control, especially with regard to flight path and attitude. It is the quality of the aircraft’s response to the pilot’s control application when maneuvering the aircraft, regardless of its stability characteristics.

 

[eman1200]

um, one is the ability to control and one is the ability to maneuver?

 

[mscard88]

um, one is the ability to control and one is the ability to maneuver?

 

[CC268]

um, one is the ability to control and one is the ability to maneuver?

Ok.

 

[jsstevens]

um, one is the ability to control and one is the ability to maneuver?

How long have you worked for Microsoft Technical Support? (An answer thats exactly correct and entirely useless is the punchline...)

 

[Capt. Geoffrey Thorpe]

um, one is the ability to control and one is the ability to maneuver?

But, which is which?

FAA sometimes defines things in the reverse of what you expect.

Movement area - where movement is restricted
Non movement area - movement is not restricted

Side slip - airplane points forward - not sideways
Forward slip - airplane points sideways, not forward

etc.

 

[Salty]

I can control a dump truck just fine, maybe even easier than a motorcycle if it has power assist everything, but I can’t manuever it like I can a motorcycle.

 

[CC268]

um, one is the ability to control and one is the ability to maneuver?

I mean...yea I get that...whether or not an examiner is going to be satisfied with that answer on a checkride? Idk...he might want something with more substance.

 

[eman1200]

I mean...yea I get that...whether or not an examiner is going to be satisfied with that answer on a checkride? Idk...he might want something with more substance.

tell him "I can show you what a lack of both are. one will probably fail my checkride, the other will ruin both of our day" and see what he says.

 

[Capt. Geoffrey Thorpe]

From the PHAK Glossary:

Controllability.
A measure of the response of an aircraft
relative to the pilot’s flight control inputs

Maneuverability.
Ability of an aircraft to change directions
along a flight path and withstand the stresses imposed upon it.

 

[kath]

Maneuverability = "Wheeeeeee!"
Controllability = <terrified scream>

 

[CC268]

From the PHAK Glossary:

Controllability.
A measure of the response of an aircraft
relative to the pilot’s flight control inputs

Maneuverability.
Ability of an aircraft to change directions
along a flight path and withstand the stresses imposed upon it.

Thanks...close to the PHAK Chapter 5 definitions, but "ability of an aircraft to change directions" is better than "it's just maneuverable, man!"

 

[Skyrys62]

Controllability vs Maneuverability?

With children, you need one... if you don't have the other.



I know that's no help, sorry man. Good answer though Capt. Thorpe.

 

[Eric Gleason]

That’s not the kind of question that gets asked on a check ride.

For some examples to demonstrate the concept, think of a C-5 Galaxy. Highly controllable. The pilot has full command of the aircraft. Not very maneuverable. Turn radius the size of counties at cruise speed. Rate of roll is pnderously slow.

For the opposite end of the spectrum, think Gee Bee raceplane of the 1930s. Highly maneuverable, but just barely controllable. It was described as trying to balance a pencil (upright) on your finger tip. Lots of pilots lost their lives trying to master it.

 

[CC268]

That’s not the kind of question that gets asked on a check ride.

For some examples to demonstrate the concept, think of a C-5 Galaxy. Highly controllable. The pilot has full command of the aircraft. Not very maneuverable. Turn radius the size of counties at cruise speed. Rate of roll is pnderously slow.

For the opposite end of the spectrum, think Gee Bee raceplane of the 1930s. Highly maneuverable, but just barely controllable. It was described as trying to balance a pencil (upright) on your finger tip. Lots of pilots lost their lives trying to master it.

Idk the gouge on this examiner is that he is the "kiss of death" lol. So I'm preparing for the worst.

That is a good practical example and was more along the lines of what I was looking for.

Thanks!

 

[-KLB-]

Maneuverability: what the plane is capable of
Controlability: how readily an average pilot can make it do what it is capable of

 

[CC268]

Maneuverability: what the plane is capable of
Controlability: how readily an average pilot can make it do what it is capable of

Nice...that's a good way of putting it as well.

 

[gkainz]

to paraphrase "Forged in Fire" ... one is about what the <hard object> does to your knife, while the other is what your knife does to the <hard object>

 

[mondtster]

That’s not the kind of question that gets asked on a check ride.

It certainly is, at least around here. Mostly at the CFI level but it isn’t unheard of at the commercial level.

It would be in an applicant’s best interest to have some basic knowledge of aerodynamics.

 

[CC268]

It certainly is, at least around here. Mostly at the CFI level but it isn’t unheard of at the commercial level.

It would be in an applicant’s best interest to have some basic knowledge of aerodynamics.

Basic knowledge in aerodynamics is more than covered...just wanted some clarification on this specific topic that’s all.

 

[ateamer]

Maneuverability: How easily ya can whip it into a tight turn.
Controllability: It won’t get squirrely on ya and start doing stuff on its own.

 

[Hank S]

Maneuverability: what the plane is capable of
Controlability: how readily an average pilot can make it do what he wants it to do.

FTFY! Now it's better.

Maneuverability is roll rate, yaw rate, etc. High maneuverability means high rates.

Controlability = Controllable = it rolls / yaws when you want and as much as you want, and stops rolling / yawing when you want it to stop.

 

[-KLB-]

FTFY! Now it's better.

Maneuverability is roll rate, yaw rate, etc. High maneuverability means high rates.

Controlability = Controllable = it rolls / yaws when you want and as much as you want, and stops rolling / yawing when you want it to stop.

Yeah, I debated how to keep that concise, but one interpretation of the fix suggest that if a pilot wants more than the airframe is capable, it is a lack of controllability, not a limit of maneuverability.

 

[Hank S]

Yeah, I debated how to keep that concise, but one interpretation of the fix suggest that if a pilot wants more than the airframe is capable, it is a lack of controllability, not a limit of maneuverability.

Most often, bad things happen when the pilot exceeds his own limits, not the limits of the airplane.

 

[Silvaire]

I agree this isn't the kind of question that would come up on a check ride and even if it did it's something that could be discussed, maybe even debated but not something that could determine pass or fail. It comes down to splitting hairs. When I started flying the Pilot's Handbook really was a "handbook" - heck, even AD's were rarely more than a couple of paragraphs. To build it into the voluminous tome that it is today government employees must have struggled to fill pages and so we end up with unnecessarily complicated definitions of common words that everyone already knows the meaning of. This is a perfect example.

 

[Stewartb]

I spent the weekend with my Aerospace Engineering Professor buddy and I asked about stability, controllability, and maneuverability. He said this page sums it up very well. https://aviation.stackexchange.com/...ward-and-aft-cg-limits-indicative-of-the-over

He also said the topic may be viewed differently by aircraft designers who work on fly- by-wire aircraft because they focus on control feedback. I thought that was an interesting twist.

 

[Lachlan]

They’re not called “Air Traffic Maneuver” up there in the Maneuver Tower, ya know.

 

[Cogito]

Can anyone think of a plane that is controllable, but not maneuverable, and vice versa? Also, my practice CFI student wants to know what purpose this distinction serves, is it just pedantic? I didn't (yet) have a good explanation.
Thanks (on this old thread) for the help.
-C

 

[dtuuri]

Can anyone think of a plane that is controllable, but not maneuverable, and vice versa? Also, my practice CFI student wants to know what purpose this distinction serves, is it just pedantic? I didn't (yet) have a good explanation.
Thanks (on this old thread) for the help.
-C

I would be thinking fighter plane characteristics. The more "stable" the plane, the harder to control. A less stable plane is a dream to fly because it doesn't fight you with a will of its own, but if it isn't "maneuverable", due to design strength, you could pull the wings off.

 

[Cogito]

Maneuverability (or Controllability) vs. Stability is easy, an F-16 vs. a Cessna, and the reasons for the difference is also elementary; Maneuverable Dogfighting vs. Stable Training. What my student and I are looking for is an example of Maneuverability vs. Controllability if anyone can help.

 

[dmspilot]

I don't think the FAA definitions are confusing, but keep in mind that maneuverability is more of an abstract concept that takes into account the multiple factors. It really can't be simplified anymore than how it's described in the PHAK. Meanwhile, controllability can be measured (amount of attitude change vs. amount of control movement).

 

[dtuuri]

Maneuverability (or Controllability) vs. Stability is easy, an F-16 vs. a Cessna, and the reasons for the difference is also elementary; Maneuverable Dogfighting vs. Stable Training. What my student and I are looking for is an example of Maneuverability vs. Controllability if anyone can help.

Normal F-16 vs F-16 w/battle damage?

 

[Cogito]

I don't think the FAA definitions are confusing, but keep in mind that maneuverability is more of an abstract concept that takes into account the multiple factors. It really can't be simplified anymore than how it's described in the PHAK. Meanwhile, controllability can be measured (amount of attitude change vs. amount of control movement).

The concepts are well defined in the PHAK glossary, I agree. Is there a plane which is Controllable but not Maneuverable? I'm trying to think of an illustrative example to teach a primary student. Perhaps there isn't one.

 

[luvflyin]

The definitions in the PHAK are somewhat confusing to me. I understand controllability, but I am having a difficult time explaining maneuverability in laymans terms.

PHAK definitions:

Maneuverability—the quality of an aircraft that permits it to be maneuvered easily and to withstand the stresses imposed by maneuvers. It is governed by the aircraft’s weight, inertia, size and location of flight controls, structural strength, and powerplant. It too is an aircraft design characteristic.

Controllability—the capability of an aircraft to respond to the pilot’s control, especially with regard to flight path and attitude. It is the quality of the aircraft’s response to the pilot’s control application when maneuvering the aircraft, regardless of its stability characteristics.

I think the last few words of ‘Controllability’ tell the story. Some airplanes are so easily maneuverable that the slightest control input results in large changes. These airplanes are not as easily controlled.

 

[frfly172]

Controllability the pilots ability to make the plane maneuver the way he wants.

 

[dmspilot]

The concepts are well defined in the PHAK glossary, I agree. Is there a plane which is Controllable but not Maneuverable? I'm trying to think of an illustrative example to teach a primary student. Perhaps there isn't one.

B747

 

[dmspilot]

I think the last few words of ‘Controllability’ tell the story. Some airplanes are so easily maneuverable that the slightest control input results in large changes. These airplanes are not as easily controlled.

Nope, that's backward. Large changes as a result of slight control input might be described as excessive controllability, making the aircraft unstable and more difficult to fly.

 

[Tantalum]

This kind of pedantic stuff is what kills me with aviation. Would an examiner really have an issue with that?

Ugh

 

[LongRoadBob]

But, which is which?

FAA sometimes defines things in the reverse of what you expect.

Movement area - where movement is restricted
Non movement area - movement is not restricted

Side slip - airplane points forward - not sideways
Forward slip - airplane points sideways, not forward

etc.

with you on movement area, but for slips...you slip to the side, you slip forward. Seems consistent and right.
If I stand facing something and move to the side (slipping sideways) I move to the side but still face forward. Forward (slipping by someone in a crowd) I move sideways, face at an angle but move forward.

maybe it’s subjective, but it makes sense to me. However the other one is the “fuel cutoff”, when they tell us in the checklist to move it to ON, literally would mean the fuel is cut off...if it were called fuel supply valve on would be supplying fuel, off not supplying but a “cut off” valve when engaged is doing its job, cutting off fuel.

 

[LongRoadBob]

I would be thinking fighter plane characteristics. The more "stable" the plane, the harder to control. A less stable plane is a dream to fly because it doesn't fight you with a will of its own, but if it isn't "maneuverable", due to design strength, you could pull the wings off.

but isn’t the last part of the control ability definition “regardless of it’s stability”?