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  #1  
Old 08-25-2008, 05:46 PM
Phlosphr Phlosphr is offline
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How low does the FAA allow small aircraft to fly over neighborhoods?

I was wondering if the FAA has a specific distance a plane is NOT allowed to fly under when in motion over neighborhoods? I know my property is in the flight path of a small airport. I've seen planes fly over when inclement weather is coming, and they are always very low. Today we had a thunderstorm blow through and a small piper cub skipped across the tree tops about 200 yards from my house. I can tell you what color shirt the pilot was wearing. He must have been 10 feet above the tops of the trees...if that.

Is that illegal?
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  #2  
Old 08-25-2008, 06:06 PM
Johnny L.A. Johnny L.A. is online now
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Sec. 91.119 - Minimum safe altitudes: General.
Quote:
Except when necessary for takeoff or landing, no person may operate an aircraft below the following altitudes:

(a) Anywhere. An altitude allowing, if a power unit fails, an emergency landing without undue hazard to persons or property on the surface.

(b) Over congested areas. Over any congested area of a city, town, or settlement, or over any open air assembly of persons, an altitude of 1,000 feet above the highest obstacle within a horizontal radius of 2,000 feet of the aircraft.

(c) Over other than congested areas. An altitude of 500 feet above the surface, except over open water or sparsely populated areas. In those cases, the aircraft may not be operated closer than 500 feet to any person, vessel, vehicle, or structure.

(d) Helicopters. Helicopters may be operated at less than the minimums prescribed in paragraph (b) or (c) of this section if the operation is conducted without hazard to persons or property on the surface. In addition, each person operating a helicopter shall comply with any routes or altitudes specifically prescribed for helicopters by the Administrator.
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Old 08-25-2008, 06:09 PM
mnemosyne mnemosyne is offline
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IANAPilot, but I know that the general rules you are looking for would be found in the Federal Aviation Regulations (FARs) for the USA and the CARs for Canada. Most countries have similar sets of standards.

Part 91.119 states:
Quote:
Sec. 91.119

Minimum safe altitudes: General.

Except when necessary for takeoff or landing, no person may operate an aircraft below the following altitudes:
(a) Anywhere. An altitude allowing, if a power unit fails, an emergency landing without undue hazard to persons or property on the surface.
(b) Over congested areas. Over any congested area of a city, town, or settlement, or over any open air assembly of persons, an altitude of 1,000 feet above the highest obstacle within a horizontal radius of 2,000 feet of the aircraft.
(c) Over other than congested areas. An altitude of 500 feet above the surface, except over open water or sparsely populated areas. In those cases, the aircraft may not be operated closer than 500 feet to any person, vessel, vehicle, or structure.
(d) Helicopters. Helicopters may be operated at less than the minimums prescribed in paragraph (b) or (c) of this section if the operation is conducted without hazard to persons or property on the surface. In addition, each person operating a helicopter shall comply with any routes or altitudes specifically prescribed for helicopters by the Administrator.
If the pilot was operating under IFR:
Quote:
Sec. 91.177

Minimum altitudes for IFR operations.

[(a) Operation of aircraft at minimum altitudes. Except when necessary for takeoff or landing, no person may operate an aircraft under IFR below--
(1) The applicable minimum altitudes prescribed in parts 95 and 97 of this chapter. However, if both a MEA and a MOCA are prescribed for a particular route or route segment, a person may operate an aircraft below the MEA down to, but not below, the MOCA, provided the applicable navigation signals are available. For aircraft using VOR for navigation, this applies only when the aircraft is within 22 nautical miles of that VOR (based on the reasonable
estimate by the pilot operating the aircraft of that distance); or
(2) If no applicable minimum altitude is prescribed in parts 95 and 97 of this chapter, then--
(i) In the case of operations over an area designated as a mountainous area in part 95 of this chapter, an altitude of 2,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown; or
(ii) In any other case, an altitude of 1,000 feet above the highest obstacle within a horizontal distance of 4 nautical miles from the course to be flown.]
(b) Climb. Climb to a higher minimum IFR altitude shall begin immediately after passing the point beyond which that minimum altitude applies, except that when ground obstructions intervene, the point beyond which that higher minimum altitude applies shall be crossed at or above the applicable MCA.
Depending on the category of aircraft, there are likely other parts and subparts that apply (general aviation vs commercial aviation, etc). In the case of your Piper coming in low, it might have been the safest way to get down to avoid the storm... overall, the FARs have the main purpose of ensuring safe flight, and so any action deemed necessary to ensure the safety of the flight without putting others at risk is generally acceptable in the case of an emergency or otherwise urgent landing, IIRC.

You can read the FARs here: http://rgl.faa.gov/Regulatory_and_Gu...e?OpenFrameSet
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Old 08-25-2008, 07:26 PM
Phlosphr Phlosphr is offline
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Thanks guys! Looks like he probably just wanted to get in fast and quick.
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  #5  
Old 08-25-2008, 07:36 PM
Johnny L.A. Johnny L.A. is online now
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Quote:
Originally Posted by Phlosphr
Looks like he probably just wanted to get in fast and quick.
In a Cub? *LMAO*
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  #6  
Old 08-25-2008, 08:42 PM
Richard Pearse Richard Pearse is offline
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Touching on what mnemosyne said. There's a general "get out of jail free" clause in most aviation authorities regulations which permit the pilot to break the rules if doing so is necessary to ensure the safe operation of the aircraft. The idea of it is that you must plan the flight such that you will operate within the rules, however if during the flight something unexpected happens and you're left in a position where continuing to follow the rules would be dangerous, you may take whatever actions are required to ensure your safety. In your case it may be that the pilot was trying to maintain visual flight conditions beneath cloud (flying in cloud can kill pilots pretty quickly if they're not equipped or trained to do it.) Or it may just be that he was toodling around in a cub casually breaking the rules and was hoping no one would notice, that happens from time to time too.
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  #7  
Old 08-25-2008, 09:49 PM
Phlosphr Phlosphr is offline
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Quote:
Originally Posted by Johnny L.A.
In a Cub? *LMAO*
Ok...lumbering along...he was probably doing 50-60mph.

He was wearing a red shirt BTW. HA!
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  #8  
Old 08-26-2008, 02:55 AM
GusNSpot GusNSpot is offline
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Pipeline patrol has a FAA wavier so they can fly low legally Out in west Texas I would pull up to clear the fences... . Aerial applicators (crop dusters) also.

In an emergency, you do what you have to do. If you die, they can't do much more to you. If you live, you sometimes have some 'splainin' to do.
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Old 08-26-2008, 04:20 AM
Broomstick Broomstick is offline
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Yes, I was going to mention the "explaining" part. After landing in someone's backyard (alright, it was a farmer, he had a HUGE backyard) due to an unexpected weather change I did have to have a "conversation" with the Authorities, which wasn't a pleasant 40 minutes, but they agreed I had taken a wise course (and thanked me for not burdening them with dead pilot paperwork).

Being close to an airport is somewhat problematic, as airplanes must of necessity pass through low altitudes while landing, and once in awhile approach lower than usual for one reason or another. "Just above treetops" may be acceptable, although actually hitting the trees is not.
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Old 08-26-2008, 12:40 PM
Shamozzle Shamozzle is offline
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Most of us have seen this, but I'll throw it out there one more time.
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  #11  
Old 08-26-2008, 01:34 PM
Magiver Magiver is offline
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Quote:
Originally Posted by Shamozzle
Most of us have seen this, but I'll throw it out there one more time.
Based on a 49" tire height that looks like a 16-20 foot clearance over the beach.

Sounds like the pilot got caught in bad weather. The general rule for T-storms is to assume there is hail inside the cell. Just flying near a freshet on a hot day can be an experience in convective turbulence so staying away from anything producing lightning is a pretty good idea.
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  #12  
Old 08-26-2008, 03:35 PM
Engywook Engywook is offline
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Quote:
Originally Posted by Johnny L.A.
Except when necessary for takeoff or landing, no person may operate an aircraft below the following altitudes:
....
(b) Over congested areas. Over any congested area of a city, town, or settlement, or over any open air assembly of persons, an altitude of 1,000 feet above the highest obstacle within a horizontal radius of 2,000 feet of the aircraft.
....
So where does that put somebody flying into San Diego? Downtown's scary close to the runway... I don't think you can land there without being less than 2000 feet away from obstacles taller than your altitude.
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Old 08-26-2008, 03:47 PM
gazpacho gazpacho is offline
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Quote:
Originally Posted by Engywook
So where does that put somebody flying into San Diego? Downtown's scary close to the runway... I don't think you can land there without being less than 2000 feet away from obstacles taller than your altitude.
Looking at google maps I don't think the tall buildings are within 2000 feet of the normal landing pattern.
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  #14  
Old 08-26-2008, 04:25 PM
brad_d brad_d is offline
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There's a parking garage just off the east end of the runway at San Diego that looks mighty perilous when driving by on I-5.

According to Wikipedia, the hills east of the airport have always presented some obstacle, requiring a steeper-than-normal descent (376, rather than 317, feet per mile). The parking garage, built later, was apparently made as tall as was permitted. Says the article, "Aircraft clear the parking structure by the required 109 feet."
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  #15  
Old 08-26-2008, 04:57 PM
Richard Pearse Richard Pearse is offline
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Quote:
Originally Posted by Engywook
So where does that put somebody flying into San Diego? Downtown's scary close to the runway... I don't think you can land there without being less than 2000 feet away from obstacles taller than your altitude.
The rules only apply when you are not landing or taking off. For large aircraft, their takeoff weight is regulated so they can takeoff, having suffered an engine failure, and still climb clear of obstacles, however the required clearance from obstacles in this phase of flight is quite low (50 feet in the Australian rules.)

Also, 2000' is only a third of a nautical mile, not very far.

Last edited by Richard Pearse; 08-26-2008 at 04:58 PM..
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  #16  
Old 08-26-2008, 06:16 PM
Johnny L.A. Johnny L.A. is online now
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Quote:
Originally Posted by Engywook
So where does that put somebody flying into San Diego? Downtown's scary close to the runway... I don't think you can land there without being less than 2000 feet away from obstacles taller than your altitude.
1920s Style "Death Ray" covered it, but here's the relevant part of the first reply:
Quote:
Except when necessary for takeoff or landing, no person may operate an aircraft below the following altitudes:
So you can get closer then.
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  #17  
Old 11-19-2011, 10:40 AM
zocanta zocanta is offline
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Dear Phlosphr,
As a pilot for 25 years I can certainly answer your question.
The incident you describe sounds suspicious from a legal standpoint. The minimum en-route altitude for all aircraft is either 500 or 1000 feet above ground level. Which of these applies depends on the spacing of the houses below as an indication of the population density below; low population density, lower altitude.
There are exceptions. The most common is approach to landing. If the aircraft you saw was approaching an airport or intending to land in a field, he/she is in no way restricted as to altitude. The other exception that could apply here is that the pilot in command may make his own rules in any kind of emergency, though an explanation may be required later.
Today, it may be hard to read the tail number on an airplane. Though international rules require 12” “N” numbers on each side of the plane, this country requires only 4” numbers. Since these numbers are painted on, one must think long and hard about wheather he/she will ever want to fly to Canada or Mexico as that would not be possible with smaller than 12” numbers. So, if you can read the numbers, you can complain.
Hope this helps!
Zocanta
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