Flap handle

How to keep the Cessna 170 flying and airworthy.

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ddr36d
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Flap handle

Post by ddr36d »

Low cost solution to reach the 10 & 20 degree flap settings. I consider this to be a minor change per Part 21.93(a)
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cessnut
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Re: Flap handle

Post by cessnut »

I believe that would be considered an alteration to a control, not a change in type design, thus subject to 43 App. A.
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redacted
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Re: Flap handle

Post by redacted »

The EZ Flap handle is sold under an STC. https://www.aircraftspruce.com/catalog/ ... ezflap.php
Nathaniel Perlman
1952 170B
N2282D S/N 20434
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Bruce Fenstermacher
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Re: Flap handle

Post by Bruce Fenstermacher »

What is this handle for?
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voorheesh
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Re: Flap handle

Post by voorheesh »

Possible minor alteration to the trim wheel? :D
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Bruce Fenstermacher
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Re: Flap handle

Post by Bruce Fenstermacher »

voorheesh wrote:Possible minor alteration to the trim wheel? :D
The flap handle addition might be considered a minor alteration depending on what (v) Control means. Someplace I seem to remember the flaps not being a primary control such as a aileron or elevator, and thus might not be considered a control. And then it looks like this device only enhances the ability of some operators to operate the flap handle which it appears could be operated normally with or without the device installed. Gee wiz it's hard to write a good all in compassing, clear and concise regulation. Of course we wouldn't be happy if it was either. 8O

Code: Select all

(a) Major alterations -
(1) Airframe major alterations. Alterations of the following parts and alterations of the following types, when not listed in the aircraft specifications issued by the FAA, are airframe major alterations:
(i) Wings.
(ii) Tail surfaces.
(iii) Fuselage.
(iv) Engine mounts.
(v) Control system.
(vi) Landing gear.
(vii) Hull or floats.
(viii) Elements of an airframe including spars, ribs, fittings, shock absorbers, bracing, cowling, fairings, and balance weights.
(ix) Hydraulic and electrical actuating system of components.
(x) Rotor blades.
(xi) Changes to the empty weight or empty balance which result in an increase in the maximum certificated weight or center of gravity limits of the aircraft.
(xii) Changes to the basic design of the fuel, oil, cooling, heating, cabin pressurization, electrical, hydraulic, de-icing, or exhaust systems.
(xiii) Changes to the wing or to fixed or movable control surfaces which affect flutter and vibration characteristics.
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johneeb
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Re: Flap handle

Post by johneeb »

Bruce Fenstermacher wrote:What is this handle for?
DSCN1256.jpg
In drift cars that would be a bump brake :-)
John E. Barrett
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ddr36d
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Re: Flap handle

Post by ddr36d »

Bruce, that other handle is for the hydraulic ski pump. You are right that the purpose of this handle is to make it easier to get to the first two flap settings and it can be used or not. I don't have inertia reel shoulder harnesses which makes it necessary to loosen it to reach the flap lever. During takeoff and landing this is not the best thing to do. I think this covered under Part 21.93(a),"A minor change is one that has no appreciable effect on the weight, balance, structural strength, reliability, operational characteristics, or other characteristics affecting the airworthiness of the product." I see no reason to spend $499 for the EZ flap when I did this for less than $15. Think the same goes for Door Stewards for $430 when you can buy the gas struts for less than $20 ea.
voorheesh
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Re: Flap handle

Post by voorheesh »

Flaps, leading edge devices, trim systems are considered “secondary” controls. They enhance or ease the pilot’s control of the airplane. They are part of the aircraft control system so would come under the description of major alterations in Part 43. Some will certainly argue with that, but my experience with applying FAA regulations is to stick with the plain language, as vague or ambiguous as it may seem. In this case the use of the word “control”, without a modifier, means exactly that. Any device, primary or secondary, used to control the airplane.

Regarding the modification in the picture, my opinion is that it is a minor enhancement that does not appear to change the function of the flap handle. It appears that it could be installed or removed without affecting the functionality of the handle. Therefore, it would not be considered to “alter” the “control” in question. Since it is attached, it would require a logbook entry by a certified technician (probably). The fact that a nearly identical system is available that is subject of an STC, is (to me) evidence that the mere existence of an STC does not dictate that the modification is a major alteration.
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Re: Flap handle

Post by voorheesh »

More thoughts on this: An A&P should think twice before signing any record of installation of this device because of the liability attached to his/her signature. So another recommendation might be for the owner/pilot to take responsibility for both installation and ongoing operation. With or without logbook entry. This after making sure that the device is reliable and won’t interfere with safe operation of the aircraft.

Now let’s say some official questions the device and claims it is “illegal” or lacks proper “approval”. The easy remedy is to just remove it, which according to the OP takes 15 minutes. Case closed.
Another possibility is to challenge the official and have him/her “prove” that some form of approval is necessary. That might be a heavy lift for that official and I believe the pilot here would prevail.

I have seen similar modifications where the pilot removes them during annual inspections so the IA isn’t put on the spot. But I know of IAs who wouldn’t blink at the device as illustrated here. That’s aviation for you.
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cessnut
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Re: Flap handle

Post by cessnut »

Whether or not it is an alteration is subject to the opinion of the person signing it off. My point was that using Part 21 as a basis for approval does not apply.
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mit
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Re: Flap handle

Post by mit »

redacted wrote:The EZ Flap handle is sold under an STC. https://www.aircraftspruce.com/catalog/ ... ezflap.php

Seems like the guy that made that use to be on here and other Aviation boards. I remember some fireworks on the discussions.
Tim
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mmcmillan2
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Re: Flap handle

Post by mmcmillan2 »

Nice job! Dress her up with some tennis racket grip tape and round off the edges.
170B owner, KCFD, CFI(I), ATP Multi
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GAHorn
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Re: Flap handle

Post by GAHorn »

mit wrote:
redacted wrote:The EZ Flap handle is sold under an STC. https://www.aircraftspruce.com/catalog/ ... ezflap.php

Seems like the guy that made that use to be on here and other Aviation boards. I remember some fireworks on the discussions.
Yes…there were some fireworks…. most of them because he tried to use Our Forums for HIS Free advertising outlet…. and the rest of the argument centered around how Ugly it looked.
'53 B-model N146YS SN:25713
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An originality nut (mostly) for the right reasons. ;)
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