Altitude Prudence

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Randall45

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Randall
Now that I have my PPL, I was wondering how to be most safe when flying over populous areas. I have always flown over desolate farms with ample options for fields in which to land. But now I'd like to--with friends and such--fly over various towns and drawn out cities for sight seeing.

Everyone knows the 1,000' above tallest obstacle and 500' above the surface and radius from anything manmade...

But the precise definition of "congested area" is undefined and I'd like to know from you experienced pilots what your rule is. And, if the engine were to fail, and you were surrounded by dense inhabitance, what would you do to mitigate disaster?
 
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Just try to make sure you can glide to a safe landing area.

Or are you asking about low level flying?




Randall45 said:
And, if the engine were to land, and you were surrounded by dense inhabitance, what would you do to mitigate disaster?
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Whatever you do, do not stall it. Fly it into trees or houses if you have to, do not stall.
 
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Not low level. Just like 1000agl and above
 
Randall45 said:
Not low level. Just like 1000agl and above
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1000ft AGL is kinda low level. I don't recommend cruising bellow 2000ft AGL without proper training.

Since your asking, a few quick tips. Recon for towers and power lines in advance, power lines will be essentially invisible as your flying. If you live around mountains keep in there may be power lines between mountain tops.
And again, for a cruise altitude of 1000ft AGL, get some proper training. There is nothing in the PPL syllabus that teaches you to safely cruise at that altitude.
 
Perfect advice! I didn't plan on going to 1000agl, but I wanted to put that out there to test the waters and elicit the perfect response you just gave!!
 
Randall45 said:
Perfect advice! I didn't plan on going to 1000agl, but I wanted to put that out there to test the waters and elicit the perfect response you just gave!!
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So yeah, if you live around flat terrain, 2000ft AGL should be relatively safe.
 
Randall45 said:
Now that I have my PPL, I was wondering how to be most safe when flying over populous areas. I have always flown over desolate farms with ample options for fields in which to land. But now I'd like to--with friends and such--fly over various towns and drawn out cities for sight seeing.

Everyone knows the 1,000' above tallest obstacle and 500' above the surface and radius from anything manmade...

But the precise definition of "congested area" is undefined and I'd like to know from you experienced pilots what your rule is. And, if the engine were to land, and you were surrounded by dense inhabitance, what would you do to mitigate disaster?
Click to expand...

It is defined, for VFR:

Minimum Safe Altitude (MSA) FAR Part 91 § 119,

  1. Anywhere: an altitude allowing a safe emergency landing without undue hazard to person or property on the ground;
  2. Over Congested Areas: an altitude of 1,000 feet above the highest obstacle within a horizontal distance of less than 2,000 feet;
  3. Over Populated Areas: an altitude of 500 feet AGL;
  4. Over Open Water or Sparsely Populated Areas: an altitude allowing for a linear distance greater than 500 feet from any person, vessel, vehicle, or structure;
You should consider an urban area or city to be Congested areas.
You should consider rural areas with houses far apart to be Populated areas.


IFR is a different set of rules.
 
For more applicability, is there a general rule of thumb for how high above the MEF?
 
Randall45 said:
For more applicability, is there a general rule of thumb for how high above the MEF?
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MEF can be as low as 100 feet above the highest point in the sectional quadrangle. if it's an object, then use the congested rule, if its terrain and sparsely populated, then use the 'populated' rule of 500 feet.
 
MachFly said:
1000ft AGL is kinda low level. I don't recommend cruising bellow 2000ft AGL without proper training.

Since your asking, a few quick tips. Recon for towers and power lines in advance, power lines will be essentially invisible as your flying. If you live around mountains keep in there may be power lines between mountain tops.
And again, for a cruise altitude of 1000ft AGL, get some proper training. There is nothing in the PPL syllabus that teaches you to safely cruise at that altitude.
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Ahhhh...what do you call downwind pattern altitude?
 
Randall45 said:
But the precise definition of "congested area" is undefined and I'd like to know from you experienced pilots what your rule is.
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I don't really have one to offer, but you should know the FAA does outside the regulations, and they are pretty loose . From some NTSB Orders on the subject:

http://www.ntsb.gov/legal/o_n_o/docs/Aviation/3646.pdf
Respondents claim, to the contrary, that Shepard Mesa is not such an area. Although the Administrator's reply inexplicably fails to address this claim, it is without foundation in case law. See, e.g., Administrator v. Harkcom, 35 C.A.B. 934, 937 (1962), and cases cited there. Thus, the Shepard Mesa subdivision -- comprised of a minimum of 20 houses, in an area approximately .5 mi. x .66 mi. -- would qualify as a congested area.

http://www.ntsb.gov/legal/o_n_o/docs/Aviation/3693.PDF
...you operated or caused to be operated N4709P, over a congested area of Malibu, namely Civic Center Way, at an altitude of 250 feet AGL [above ground level], descending over a Hughes Market and the Malibu Country Market, flaps down and slow speed, until it reached an altitude of about 100 feet AGL, headed toward a field just south of the Court House at 23525 Civic Center Way. When at an altitude of about 100 feet AGL over the Malibu Country Market, you began a climb out. There were many shoppers in the markets and adjacent parking lots.

http://www.ntsb.gov/legal/o_n_o/docs/Aviation/4080.PDF
During the course of the above flight you made several low passes over a congested area, specifically the Pearce Ford Tower at Western Kentucky University, Bowling Green, Kentucky,...

http://www.ntsb.gov/legal/o_n_o/docs/Aviation/4188.PDF
In the Board's view, even if Interstate 5, a major California freeway, is not "bumper to bumper" on a late Saturday afternoon, moderate traffic in every lane still renders it "congested," for purposes of the regulation. See also Administrator v. Dutton, NTSB Order No. EA-3204 (1990) (Moderate traffic on a highway at 12:55 p.m. is a congested area for purposes of the minimum safe altitude regulation).

http://www.ntsb.gov/legal/o_n_o/docs/Aviation/4210.PDF
...respondent operated his Cessna 172 aircraft within 100-200 feet of the ground in the Revere-Saugus, MA area on July 11, 1992, in the vicinity of a large regatta (including "Tall Ships") commemorating the 500th anniversary of Columbus' voyage. The nearby ground and water areas were congested, and respondent would not have been able to make a safe emergency landing.

BTW, I think the first one cited (in which a clump of 20 houses is considered a "congested area") is the strictest interpretation of the term "congested area" in that context, and one which should be weighed carefully by any pilot considering flight below 1000 AGL.

And, if the engine were to land, and you were surrounded by dense inhabitance, what would you do to mitigate disaster?
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Aim for something soft? I guess it's not something one can put into words in advance, just a decision you make based on the no doubt unique circumstances at the time.
 
CTLSi said:
It is defined, for VFR:

Minimum Safe Altitude (MSA) FAR Part 91 § 119,

  1. Anywhere: an altitude allowing a safe emergency landing without undue hazard to person or property on the ground;
  2. Over Congested Areas: an altitude of 1,000 feet above the highest obstacle within a horizontal distance of less than 2,000 feet;
  3. Over Populated Areas: an altitude of 500 feet AGL;
  4. Over Open Water or Sparsely Populated Areas: an altitude allowing for a linear distance greater than 500 feet from any person, vessel, vehicle, or structure;
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Unfortunately, that's not what that section says. I quote directly by cut-and-paste from the FAA's Regulatory and Guidance Library, and you'll see there's nothing called a "Populated Area" in that section.

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.
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CTLSi said:
You should consider an urban area or city to be Congested areas.
You should consider rural areas with houses far apart to be Populated areas.
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First, there's no such thing in the relevant section of the FAR's as a "Populated Area". Second, if you read the NTSB Orders cited above, you'll see a rural area with houses may still be a "congested area", and there is nothing in the regulations or any case I can find which says just how far apart houses must be in a rural area before it is considered a "sparsely populated area".

CTLSi said:
IFR is a different set of rules.
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There is nothing in 91.119 or any other section limiting 91.119's applicability to VFR operations.
 
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Randall45 said:
And, if the engine were to land, and you were surrounded by dense inhabitance, what would you do to mitigate disaster?
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If think if the engine were to land without the plane, it'd be ****all! as the Aussie's say .... :lol:
 
txflyer said:
If think if the engine were to land without the plane, it'd be ****all! as the Aussie's say .... :lol:
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I just erupted into uncontrollable laugher. Perhaps I should proofread this a little? :yes:

Or perhaps I meant that. :dunno: If the engine were to make an incredible, smooth landing on the road below me, should I applaud its precision airmanship, or should I be upset that it made an unexpected exit? :confused:
 
MachFly said:
1000ft AGL is kinda low level. I don't recommend cruising bellow 2000ft AGL without proper training.

Since your asking, a few quick tips. Recon for towers and power lines in advance, power lines will be essentially invisible as your flying. If you live around mountains keep in there may be power lines between mountain tops.
And again, for a cruise altitude of 1000ft AGL, get some proper training. There is nothing in the PPL syllabus that teaches you to safely cruise at that altitude.
Click to expand...

What proper training should I get? I generally cruise in the Flybaby at 800 to 1000 ft.
 
jesse said:
What proper training should I get? I generally cruise in the Flybaby at 800 to 1000 ft.
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For one you didn't just get your PPL. Two, you're still alive so you must be doing something right. And three, as far as I know the Flybaby isn't that fast so you have plenty of time to react.

Regarding the type of training I'm talking about. Look at the military for example, they often fly low so they get proper training. Civilians usually try and either learn before they run out of luck, or run out of luck before they learn. Because in the civilian world no one really goes through proper low alt training.
 
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MachFly said:
You don't cruise in downwind.
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I set power and pitch on the downwind and....just wait. What do you do?

dictionary.reference.com said:
cruise
/kruz/ Show Spelled [krooz] Show IPA
verb (used without object), cruised, cruis·ing.
1. to sail about on a pleasure trip.
2. to sail about, as a warship patrolling a body of water.
3. to travel about without a particular purpose or destination.
4. to fly, drive, or sail at a constant speed that permits maximum operating efficiency for sustained travel.
5. to travel at a moderately fast easily controllable speed: cruising along the highway enjoying the scenery.
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MachFly said:
For one you didn't just get your PPL. Two, you're still alive so you must be doing something right. And three, as far as I know the Flybaby isn't that fast so you have plenty of time to react.

Regarding the type of training I'm talking about. Look at the military for example, they often fly low so they get proper training. Civilians usually try and either learn before they run out of luck, or run out of luck before they learn. Because in the civilian world no one really goes through proper low alt training.
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Please define this "proper training".
 
Realistically, you will want to be well above 2000' anyway - at least just after takeoff / before landing. "bumps" can get pretty interesting down low. I've found myself at 10500' a couple of months ago to find something that was "enjoyable" (ish).
 
I don't like cruising below 3,000 feet AGL personally, unless it's a really short flight. That isn't to say I'm normally going to give mountain ridges and passes 3,000 feet of clearance.
 
Ron Levy said:
Unfortunately, that's not what that section says. I quote directly by cut-and-paste from the FAA's Regulatory and Guidance Library, and you'll see there's nothing called a "Populated Area" in that section.

First, there's no such thing in the relevant section of the FAR's as a "Populated Area". Second, if you read the NTSB Orders cited above, you'll see a rural area with houses may still be a "congested area", and there is nothing in the regulations or any case I can find which says just how far apart houses must be in a rural area before it is considered a "sparsely populated area".

There is nothing in 91.119 or any other section limiting 91.119's applicability to VFR operations.
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Populated area is clear enough. It's an area with people on the ground, but sparsely so.

The lower altitudes are intended for areas where you don't disturb, endanger or upset people on the ground. Places like where cows, sheep, empty fields, or open desert exist...do you need a hand drawing?
 
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CTLSi said:
Populated area is clear enough. It's an area with people on the ground, but sparsely so.

The lower altitudes are intended for areas where you don't disturb, endanger or upset people on the ground. Places like where cows, sheep, empty fields, or open desert exist...do you need a hand drawing?
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Actually, if you read Ron's examples, it ain't clear at all.

One of them is I-5. You've clearly never been there if you think a sane person would call that "congested." It's almost completely empty south of Tracy for 300+ miles, and again north of Sacramento for another 300+ miles in the other direction.

And I've definitely seen crop-dusters less than 500 feet from the interstate. In season, several dozen at a time. Even the CHP pushes that rule on occasion.
 
Sac Arrow said:
I don't like cruising below 3,000 feet AGL personally, unless it's a really short flight. That isn't to say I'm normally going to give mountain ridges and passes 3,000 feet of clearance.
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:yeahthat:
 
MachFly said:
Just try to make sure you can glide to a safe landing area.



Or are you asking about low level flying?













Whatever you do, do not stall it. Fly it into trees or houses if you have to, do not stall.
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I've been wondering about this, so what speed should you be at when you hit the tree canopy or house?

Clearly the normal 1.3 Vso is going to be fast. JUST above stall? Something else?
 
dans2992 said:
I've been wondering about this, so what speed should you be at when you hit the tree canopy or house?

Clearly the normal 1.3 Vso is going to be fast. JUST above stall? Something else?
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As slow as possible while maintaining positive control. Keep in mind that slow flight will feel different without engine power because you won't have accelerated airflow over your controls and winds.

Statistically engine out "crashes" in non-hospitable terrain turn out a lot more fatal if the aircraft stalled before touchdown.
 
A slow (yet still flying) speed would result in a moderately steep approach angle, with no energy left to flare, right? Would that higher vertical speed be an issue?

If I were doing a forced landing into a forest, would I be better flying a stable descent into the canopy tops at minimum speed (yet steeper), or flying normal approach speed, then flaring over the canopy top and "settling" (not stalling) into the canopy when minimum speed is reached?
 
dans2992 said:
A slow (yet still flying) speed would result in a moderately steep approach angle, with no energy left to flare, right? Would that higher vertical speed be an issue?

If I were doing a forced landing into a forest, would I be better flying a stable descent into the canopy tops at minimum speed (yet steeper), or flying normal approach speed, then flaring over the canopy top and "settling" (not stalling) into the canopy when minimum speed is reached?
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Well, most forests don't have uniform tops. At some point, you'll have to split trees. Do this just above MCA.

And it does happen successfully on occasion. Last week, there was a CAP search in northern California for a missing Ercoupe over the southern Cascades (mountainous, heavily forested) whose pilot did all that just fine, and walked away with cuts, bruises, and a totaled Ercoupe.
 
For "most safe", it would be as high as possible.

It's up to you. If you fly low (1000') over populated areas, you are less likely to be able to find a safe landing in event of an engine out. Yet some pilots do it all the time. It's legal. Some pilots put engine outs in the back of their mind and just "do it".

And it's not like you have to do it the same all the time. Feeling like taking some risk? Fly low, take chances. Feeling like a safety freak? File a flight plan, get flight following.

If you fly higher, you will have more options.

As for me, I avoid flying over populated areas. I save up up my risk taking for flying in the mountains. Colorado is so beautiful, I can't help it!

Altitude is safety. So is fuel. Makes you feel safer too.

Randall45 said:
Now that I have my PPL, I was wondering how to be most safe when flying over populous areas. I have always flown over desolate farms with ample options for fields in which to land. But now I'd like to--with friends and such--fly over various towns and drawn out cities for sight seeing.

Everyone knows the 1,000' above tallest obstacle and 500' above the surface and radius from anything manmade...

But the precise definition of "congested area" is undefined and I'd like to know from you experienced pilots what your rule is. And, if the engine were to fail, and you were surrounded by dense inhabitance, what would you do to mitigate disaster?
Click to expand...
 
"the sky above you does you no good." -- an older pilot friend
 
Ron Levy said:
One of the Three Most Useless Things in Flying, the other two being "runway behind you" and "fuel in the fuel truck".
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I thought it was "runway behind you, altitude above you, and half a second ago."
 
Congested area is pretty common sense, do we really need FAA to come up with a clear definition and make our lives harder.
 
TommyG said:
Congested area is pretty common sense, do we really need FAA to come up with a clear definition and make our lives harder.
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Apparently we do, or else the events in those cases I quoted would never have occurred.

"We have met the enemy, and he is us." -- Walt Kelly (in the voice of Pogo)
 
Something the FAAST guys were covering last year was bird strike awareness. Numbers showed something like 90% of all bird strikes were below 2,000ft AGL. And then a student and instructor walked in from landing after a bird strike while in the pattern. Made quite a mess.
 
TommyG said:
Congested area is pretty common sense, do we really need FAA to come up with a clear definition and make our lives harder.
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Your and mine definition of "congested" may be completely different so there should be something that can/will standardize it.
 
If the spray from the water gets on the windshield, I climb.
If I can hear people yell at me, I climb.
Joking. Mostly.
I do like to fly low, at times.

One of the things that always intrigued me about the height and distance rules was the landing clause.
Nothing applies if you are landing, so my excuse is I'm always practicing emergency landings.
 
I'm in the low camp. When I fly airplanes it is generally around 1,000-2,000 AGL. Flying any higher in a slow little airplane is as boring as it gets and I fly to amuse myself. Yes I do have low altitude flight training.
 
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