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Uugh... FAR's are making my head spin again. Where would it specify that the stall warning horn must be operative for day VFR in the 172? In the POH because it is a model specific requirement, or is it a class specific requirement that would be somewhere else in the FAR's?
[/ QUOTE ]In the case of the 172, if you go into the Equipment List in the Weight and Balance section of the POH, you'll see that it is listed with an "R" next to it, which means that it is required to be there and operating in order for the airplane to be airworthy.
I hope this doesn't sound like a rant because your question is understandable. It's the reason for the comments I just made in the other post. It's a training issue. Unless you were taught that 91.205 was a big deal, it wouldn't hurt your head.
Think about it for a moment. Forget FARs and legal interpretations. Here what the focus on 91.205 is saying:
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There is only one regulation that covers required equipment for all airplanes from a Taylorcraft (with an "electrical system" consisting of the battery in the handheld radio) up to a 767 regardless of whether it's being used to fly touch and goes around a private airfield or transport 400 paying passengers overseas.
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That concept makes =my= head spin.
FWIW, here's the standard "answer" I give to the stall warning horn quiz (it's a cut and paste):
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The Answer
The answer ultimately depends on your airplane, but the chances are excellent you may =not= legally fly the airplane without a special flight permit under 91.213(e). For illustration, since so many of us are familiar with them, I'll refer to a generic Cessna 172.
My "project" is an article that argues that the emphasis on memorizing 91.205 is a bad thing. If your answer (even if you just thought about it but didn't respond) was "yes, because the stall warning horn is not listed in 91.205", please think about how learning TOMATO FLAMES or GOOSE A CAT has misled you.
Those who started with 91.213 rather than 91.205 were on the right track. Assuming that there is no MEL for the airplane, 91.213 tells us we cannot fly with =any= inoperative equipment unless two conditions are met:
1. The inoperative equipment is not one of those that is "always required" to work - 91.213(d)(2)
AND
2. If the equipment is not "always required", it must be removed or deactivated, placarded, and logged - 91.213(d)(3).
Starting with the first condition, there are 4 groups of "always required" equipment listed in 91.213(d)(2):
(a) Required by the airworthiness regulations in effect when the aircraft was certified. - 91.213(d)(2)(I)
(b) Marked required in the equipment list - 91.213(d)(2)(ii)
(c) Required by § 91.205 (or other Part 91 rule) - 91.213(d)(2)(iii) (Notice how the one we are forced to memorize is only a very small piece of the equation)
(d) Required to work by an AD - 91.213(d)(2(iv)
Group (a) can be tough. Regulations change. The current regulations for certification of normal, utility, acrobatic and commuter aircraft are under FAR Part 23, although older Cessna models were certified under the older Civil Air Regulations (CAR) Part 3. (If someone has a copy of the CAR, I'd love to see it!) But, if you take a look at FAR 23.207, you'll find that airplanes certified under Part 23 are required to have a stall warning system.
Fortunately, as we'll see, there is an overlap between group (a) and group (b).
Group (b) is pretty easy. Look in the Weight and Balance section of a modern POH and you'll find the equipment list. In the equipment list for Cessna 172 for example. You'll find the stall warning horn clearly marked "Required".
In terms of overlap with the (a) group, you probably won't be surprised to find that if a piece of equipment was required for certification, it also appears as "Required" in the equipment list.
Do you fly an older airplane without an marked equipment list? All is not lost. Each airplane has a Type Certificate Data Sheet (TCDS) that identifies the rules under which the airplane was certified. They are available online at
www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/MainFrame?OpenFrameSet. The TCDS that applies to all 172 models through the Q series contains the requirement for a stall warning indicator.
We don't even have to get to group (c) (the one we are forced to memorize). And it wouldn't help us a bit if we did look at it.
Removal, deactivation and placarding under 91.213(d)(3) don't make any difference. Placarding only helps with equipment that isn't "always required". The stall warning horn =is= required.
BTW, for those who say, "I don't care if were legal to fly without it, =I= wouldn't", congratulations! That's really the most important step and the one that makes the difference between a pilot and someone just going for a ride.
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