Turbojets, Flaps and Towers

luvflyin

luvflyin

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Luvflyin
FAR 91.126 (c) says this:

(c)Flap settings. Except when necessary for training or certification, the pilot in command of a civil turbojet-powered aircraft must use, as a final flap setting, the minimum certificated landing flap setting set forth in the approved performance information in the Airplane Flight Manual for the applicable conditions. However, each pilot in command has the final authority and responsibility for the safe operation of the pilot's airplane, and may use a different flap setting for that airplane if the pilot determines that it is necessary in the interest of safety.

That is just a reprint from 91.xxx that was around in 1991 about Airport Traffic Areas and goes back a long way. I don't see anything else in FAR 91 that tells a Turbojet what they must use as a final flap setting. Anyone have any idea why regulating flap settings in FAR 91 would ever have been a big deal, and why just at Towered airports?

EDIT: It doesn't specify Towered airports. But why just airports in Class G airspace? What's the big deal about flaps there?

More EDIT: It’s not just Class G. Read on.
 
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luvflyin said:
FAR 91.126 (c) says this:

(c)Flap settings. Except when necessary for training or certification, the pilot in command of a civil turbojet-powered aircraft must use, as a final flap setting, the minimum certificated landing flap setting set forth in the approved performance information in the Airplane Flight Manual for the applicable conditions. However, each pilot in command has the final authority and responsibility for the safe operation of the pilot's airplane, and may use a different flap setting for that airplane if the pilot determines that it is necessary in the interest of safety.

That is just a reprint from 91.xxx that was around in 1991 about Airport Traffic Areas and goes back a long way. I don't see anything else in FAR 91 that tells a Turbojet what they must use as a final flap setting. Anyone have any idea why regulating flap settings in FAR 91 would ever have been a big deal, and why just at Towered airports?
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Where does it say anything about this being exclusive to a towered airport?
 
Ryanb said:
Where does it say anything about this being exclusive to a towered airport?
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It doesn't ... rather, it is within a section that specifically addresses operating at airports in Class G airspace:

§ 91.126 Operating on or in the vicinity of an airport in Class G airspace.

(a) General. Unless otherwise authorized or required, each person operating an aircraft on or in the vicinity of an airport in a Class G airspace area must comply with the requirements of this section.

(b) Direction of turns. When approaching to land at an airport without an operating control tower in Class G airspace -

(1) Each pilot of an airplane must make all turns of that airplane to the left unless the airport displays approved light signals or visual markings indicating that turns should be made to the right, in which case the pilot must make all turns to the right; and

(2) Each pilot of a helicopter or a powered parachute must avoid the flow of fixed-wing aircraft.
​
(c) Flap settings. Except when necessary for training or certification, the pilot in command of a civil turbojet-powered aircraft must use, as a final flap setting, the minimum certificated landing flap setting set forth in the approved performance information in the Airplane Flight Manual for the applicable conditions. However, each pilot in command has the final authority and responsibility for the safe operation of the pilot's airplane, and may use a different flap setting for that airplane if the pilot determines that it is necessary in the interest of safety.

(d) Communications with control towers. Unless otherwise authorized or required by ATC, no person may operate an aircraft to, from, through, or on an airport having an operational control tower unless two-way radio communications are maintained between that aircraft and the control tower. Communications must be established prior to 4 nautical miles from the airport, up to and including 2,500 feet AGL. However, if the aircraft radio fails in flight, the pilot in command may operate that aircraft and land if weather conditions are at or above basic VFR weather minimums, visual contact with the tower is maintained, and a clearance to land is received. If the aircraft radio fails while in flight under IFR, the pilot must comply with § 91.185.​
 
Pilawt said:
It doesn't ... rather, it is within a section that specifically addresses operating at airports in Class G airspace:

§ 91.126 Operating on or in the vicinity of an airport in Class G airspace.

(a) General. Unless otherwise authorized or required, each person operating an aircraft on or in the vicinity of an airport in a Class G airspace area must comply with the requirements of this section.

(b) Direction of turns. When approaching to land at an airport without an operating control tower in Class G airspace -

(1) Each pilot of an airplane must make all turns of that airplane to the left unless the airport displays approved light signals or visual markings indicating that turns should be made to the right, in which case the pilot must make all turns to the right; and

(2) Each pilot of a helicopter or a powered parachute must avoid the flow of fixed-wing aircraft.
​
(c) Flap settings. Except when necessary for training or certification, the pilot in command of a civil turbojet-powered aircraft must use, as a final flap setting, the minimum certificated landing flap setting set forth in the approved performance information in the Airplane Flight Manual for the applicable conditions. However, each pilot in command has the final authority and responsibility for the safe operation of the pilot's airplane, and may use a different flap setting for that airplane if the pilot determines that it is necessary in the interest of safety.

(d) Communications with control towers. Unless otherwise authorized or required by ATC, no person may operate an aircraft to, from, through, or on an airport having an operational control tower unless two-way radio communications are maintained between that aircraft and the control tower. Communications must be established prior to 4 nautical miles from the airport, up to and including 2,500 feet AGL. However, if the aircraft radio fails in flight, the pilot in command may operate that aircraft and land if weather conditions are at or above basic VFR weather minimums, visual contact with the tower is maintained, and a clearance to land is received. If the aircraft radio fails while in flight under IFR, the pilot must comply with § 91.185.​
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Yup. My post edited.
 
My guess would be for noise. Less drag, less power down final, less noise.
 
Maybe the FAA got tired of jets running off the ends of the short runways at Class G airports.
 
I have been told in the past that .126 was the Thurman Munson FAR, untrue?
 
After March 28,1977 this rule became effective for all airports at both controlled and uncontrolled airports. Paragraph 91.85 at the time had certain requirements like this for all airports with 91.87 and 91.89 adding additional requirements for towered and non-towered airports respectively.
 
Pilawt said:
The question remains, though, is that requirement for flap operation limited to Class G airports? If so, why?
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Yeah, I'm wondering what the history is on this. Something must have happened somewhere, sometime
MauleSkinner said:
Class E & Class D regs say you have to comply with 91.126.
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Ah. So they do. It’s right there in the first sentence. More edit to OP. Can I just start over?
 
luvflyin said:
Ah. So they do. It’s right there in the first sentence. More edit to OP. Can I just start over?
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It's a common mistake. I've gotten into more arguments than I can count with people who say "but that reg only applies to Class G". Unfortunately most of them continue arguing after I point out why they're wrong. :rolleyes:
 
dtuuri said:
After March 28,1977 this rule became effective for all airports at both controlled and uncontrolled airports. Paragraph 91.85 at the time had certain requirements like this for all airports with 91.87 and 91.89 adding additional requirements for towered and non-towered airports respectively.
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Do you have a link to the FAR 91 from then?
 
luvflyin said:
Do you have a link to the FAR 91 from then?
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Sorry, no. I tried to make a "Regulatory Basis" from the FAA's website for you, but that tool is worthless. I got my info from my extensive pack rat collection of historical trash.
 
dtuuri said:
Sorry, no. I tried to make a "Regulatory Basis" from the FAA's website for you, but that tool is worthless. I got my info from my extensive pack rat collection of historical trash.
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Thanks for trying. Just getting what the 91.xxx was back then, 85, and a date, 1977, led me to what I’m looking for. What I find is in ‘someone vs someone’ court dockets where the FAR shows up. @Greg Bockelman , post#9, was right that the flaps part of it was about noise. What I’m actually doing is trying to document the relationship of the old Airport Traffic Area to current FAR’s in the ‘alphabet soup airspace designation’ of today. Always wondered what flaps would have to do with that, now I know. There are airspace bust cases to, usually someone appealing suspension of their pilot certificate for busting an Airport Traffic Area, 91.85 (b), the current equivalent is of course 91.126 (d). Now what has me scratchin my head is just WTF was an Airport Traffic Area. My memory is a 5 statue mile radius from the airport up to but not including 3000 feet AGL. One of the noise cases said it was the space within the Control Zone below 2000, but that seemed to just be a toungue in cheek description. But then FAR 1.1 gets quoted in some other cases where the definition is 5 statue miles and 2000 feet. The current equivalent is of course 4 nautical and 2500 in 91.126 (d). If you had some FAR 1 lying around in your rats nest of historical trash and could get the definition of Airport Traffic Area as of early 1991 and wanted to find it I would appreciate it. Maybe even further back if it is 3000 and see if it was 2000 once.
 
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luvflyin said:
If you had some FAR 1 lying around in your rats nest of historical trash and could get the definition of Airport Traffic Area as of early 1991 and wanted to find it I would appreciate it. Maybe even further back if it is 3000 and see if it was 2000 once.
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In 1965 and 1970 it was 2,000 (not including). The 1971 revision #10 to VFR Exam-O-Grams says 3,000 (not including). I'm guessing 1970 was when it was upped.
 
dtuuri said:
In 1965 and 1970 it was 2,000 (not including). The 1971 revision #10 to VFR Exam-O-Grams says 3,000 (not including). I'm guessing 1970 was when it was upped.
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Thanks for taking the time, really appreciate it
 
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