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2,000' AGL exception


Ed Cesnalis

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Later this week I have to do a short flight, below is the vertical profile.  Travling from west to east (right to left) do you find the 2,000' exception to the 10,000' altitude limitation very useful?  How do you interpret it, can you fly above 10,000' prior to being over terrain above 8,000'?

 

 

 

 

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The only rational way to interpret the limitation is that you can fly a profile that will allow you to maintain 2000' separation from terrain.  If this means that at some point in your climb or descent you have to be over 2000' above terrain over 10,000 feet, then so be it.  If you are 2000' above terrain at 9500' and there is a 3000' higher sheer face ahead, you have to be able to initiate your climb before getting to the face, or you will be a bug splat on the mountain.

 

This seems a gray area in the FARs, but I would certainly err on the side of flight safety, you can easily justify it to the FAA if needed later.  I have heard some say that they interpret the limitation to mean 2000' above highest terrain within a couple miles in all directions, even if your flight path doesn't bring you over that high terrain.  That is a stretch, but having to climb to reasonably clear terrain by 2000' seems perfectly justifiable (FAA may disagree). 

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Originally the rule was an absolute 10,000' ceiling, now it has the 2,000 AGL exception.  They changed the rule to be less restrictive yet as written the exception offers little unless you are willing to interpret it to mean something other than altitude above ground level or you are willing to climb up ridge lines.

 

Andy, you don't have to just be over 2,000' above 10,000, you only have to be over 2,000' above 8,000+ terrain.  I can't think of any other regs that you 'interpret' to make it rational, I don't see why people think this one is different.  Of course you will not splat on the shear face you will turn away and take a longer route.

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Originally the rule was an absolute 10,000' ceiling, now it has the 2,000 AGL exception.  They changed the rule to be less restrictive yet as written the exception offers little unless you are willing to interpret it to mean something other than altitude above ground level or you are willing to climb up ridge lines.

 

Andy, you don't have to just be over 2,000' above 10,000, you only have to be over 2,000' above 8,000+ terrain.  I can't think of any other regs that you 'interpret' to make it rational, I don't see why people think this one is different.  Of course you will not splat on the shear face you will turn away and take a longer route.

 

People interpret the FARs all the time.  If it's an issue that the FAA attorneys have issued no guidance on, then there a lot of vague regs that essentially must be interpreted.  The only other alternative is to consult the FSDO, and if you consult three FSDOs on a reg you will likely get three different and contradictory answers.  

 

I'm not saying it's ideal, but there are a lot of gaps and gray spaces in the FARs that need clarification.  The Sport Pilot rules are especially weird because of all the arbitrary limits placed on Sport Pilot and LSA operations.  I agree with you that you need to plan your routes to stay legal by the strict letter of the FARs, but if a mistake is made and you end up in a tight spot, I'd rather take a slightly looser interpretation of a reg than be a grease spot.

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You are allowed to be 2K over the highest obstacle in your flight path within a reasonable distance.You can't be 200 miles away, but within 20-40 miles should not be an issue.  Part of the issue will be it takes a while just to get up there and you can't do that right next to the obstacle. There isn't anyone up there to check your license anyway.

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You are allowed to be 2K over the highest obstacle in your flight path within a reasonable distance.You can't be 200 miles away, but within 20-40 miles should not be an issue.  Part of the issue will be it takes a while just to get up there and you can't do that right next to the obstacle. There isn't anyone up there to check your license anyway.

 

To CT's point, is that your interpretation, or have you talked to somebody at FAA to confirm that?  I'm not being snarky, just genuinely curious.   

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I would go with the MEA for a given area then round up to the appropriate 500' based on direction.  I feel this supports the appropriate altitude using FAA supplied data and recommendations.

 

The local MEAs for me are 13.5, 14.6, 14.5, 14.6.  Your method would have me flying 14,500, 15,500 and 16,500.  I don't think that is even close to the sport pilot rule's intent.

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You are allowed to be 2K over the highest obstacle in your flight path within a reasonable distance...

 

If that's true why do they use the term AGL?  Do you have a reference?

 

I can make most of my flight paths go over Mt Whitney and there are similar peaks in the other directions.  I would only be limited by performance ceilings and conditions.

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The over 10,000 MSL rule is in 14 CFR § 61.315. 

 

As a Sport Pilot you may not act as PIC:

(11) At an altitude of more than 10,000
feet MSL or 2,000 feet AGL, whichever
is higher.
 
No other language is offered.  Likely the intent is they don't want Sport Pilots flying where oxygen is required, or where oxygen is a necessity.  But like Roger notes who can verify you are not a private pilot in the LSA?  Or if you have an accident or get hypoxia, then, if you survive, may have to answer for the violation.

 

So from reading that , my interpretation is, that if you are flying at 12,000 ft MSL  , its ok as long as you are 2000 ft AGL.

 

Cheers

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The rule was setup because they realised that 10k was a little limiting in some areas of the US like the Rocky Mnts or the Sierra's. I don't think they had in mind flying at 16k+. You are supposed to plan a route that allows you to stay away from any required oxygen requirements. If you have a 10k Mnt. then if need be fly at 12k. Not many need to plan a route to fly over a 14k Mnt. that you couldn't go around.

 

Ed,

You were with me over the Grand Canyon at 11.5k so why worry now?

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That was a long time ago, IIRC Erin was PIC on that flight.

 

Its not that I"m worried so much as an observer of some dumb rule-making, dumb revision and dumb interpretation.  I wish now that I would have provided some input when the rule was being amended.  AGL exceptions don't work as intended because mountains are steep, that seems fundamental to me.

 

MEA minus 1,000' would work a million times better.

 

The 10,000' ceiling with an AGL exception only comes into play in big mountains.  Big mountains often have 'venturi', lower passess between higher peaks where winds often accelerate through and rotor over the lee side.  Compliance with the rule and exception encourages you to fly in the most volatile places.  I could cross the Ritter Range strait ahead in this photo without exceeding 2,000' AGL but staying legal would increase the risk dramatically.

 

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MINIMUM EN ROUTE IFR ALTITUDE (MEA)- The lowest published altitude between radio fixes which assures acceptable navigational signal coverage and meets obstacle clearance requirements between those fixes. The MEA prescribed for a Federal airway or segment thereof, area navigation low or high route, or other direct route applies to the entire width of the airway, segment, or route between the radio fixes defining the airway, segment, or route.

 

MEA doesn't mean much to VFR flying and topography. It has to do with radio reception and thus is a function of where the radio transmitter is located in relationship to the terrain. In other words, over similar mountains, the MEA could be different based on where the transmitters are. Staying just below the MEA may give one hope one will not run into an IFR airplane with heads down in the charts, but it doesn't say much about safely clearing terrain.

 

There is a lot of speculation going on here and I've not seen anyone citing an FAA letter or Chief Counsel interpretation that permits one to do other than circle and climb when the terrain rises faster than your climb rate. Would ATC even know you were SP if you didn't tell them? I'm surprised no one said that.

 

Mountain pilots for many decades have advised approaching a ridge line at an angle (like 45°) such that with a 90° turn you are going away from the terrain as opposed to flying straight on and needing about a 135° turn to achieve the same result.

 

If one were flying a Carbon Cub, it may be that one would have enough rate of climb to handle nearly any mountain. So, the question may be somewhat aircraft dependent.

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So, given the wording when do you fly at 10k MSL, when do you fly at 2k AGL?  The answer is you fly at 10k MSL max unless you encounter a mountain, or high plain at 8,0001 MSL or higher, then you can add 2k AGL to that altitude.

 

 

That's the way I read it too.  Interesting that most everyone else reads something different.

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That's the way I read it too.  Interesting that most everyone else reads something different.

So in theory, you believe that to not bust the regulation you must do the following:

 

* Assume you are flying over a mountain range with a 2 mile wide valley,  The floor is at 7,500 and peaks on either side are 10,500

* You must following the increasing MSL as you approach the valley never going more than 2K AGL up to a max of 12,500

* Once you hit the peak you must descend to a maximum 10K

* You then following the terrain at no more than 2K AGL (if over 10K) to clear the peaks on the other side of the valley

* You max out at 12,500 on the other side, then start descent to 10K MSL or 2K AGL over the high-plains

* Repeat process for next peak/valley

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Originally the rule was an absolute 10,000' ceiling, now it has the 2,000 AGL exception. 

 

Glad someone realized some of us live at high elevation and fixed that abortion of a rule.

 

In the end, I think that what is important is getting the job done safely. If the airplane I'm in won't fly some steep pass in a 2000ft agl profile, I'm not going to fly in circles trying to gain altitude becoming a risk to other aircraft passing through that area. I'm going to get a run at it, and gain that altitude early- which is safe because it gives you time/energy to work with if something isn't going right. If the FAA honestly would rather you fly dangerously through high elevation mountains cutting it close because of a rule based on some imaginary nonsense (private pilots can fly from 12,500 to 14,000msl for up to 30min without oxygen.... but apparently sport pilots can't handle it) rather than taking a safe approach of flying a profile the airplane can handle in order to clear a pass without being a nuisance to other aircraft in the area... then I've lost all hope. I would imagine it's one of those things nobody would push if you have a realistic reason for "breaking" this rule. Maybe I'm wrong, but I would hope some common sense would be involved....

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So in theory, you believe that to not bust the regulation you must do the following:

 

* Assume you are flying over a mountain range with a 2 mile wide valley,  The floor is at 7,500 and peaks on either side are 10,500

* You must following the increasing MSL as you approach the valley never going more than 2K AGL up to a max of 12,500

* Once you hit the peak you must descend to a maximum 10K

* You then following the terrain at no more than 2K AGL (if over 10K) to clear the peaks on the other side of the valley

* You max out at 12,500 on the other side, then start descent to 10K MSL or 2K AGL over the high-plains

* Repeat process for next peak/valley

 

 

 

Your describing an east west flight across Nevada post-6-0-07150700-1402601650_thumb.png

 

To comply with the language in the sport pilot rule a sport pilot would need to repeatedly climb to clear the next ridge and then descend below 10,000' when over the valleys.

 

 

 

 

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Just stay at the proper altitude to clear your obstacles. There isn't a need to bounce up and down. So long as the distances are reasonable between obstacles. Trying to dot every "I" and cross every "T" in a reg. like this one

isn't feasible. My contact at the FAA says it wasn't really the intent.

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Just stay at the proper altitude to clear your obstacles. There isn't a need to bounce up and down. So long as the distances are reasonable between obstacles. Trying to dot every "I" and cross every "T" in a reg. like this one

isn't feasible. My contact at the FAA says it wasn't really the intent.

 

One of the local California Highway Patrol officers gave me some advice.  "Keep it under 80 and you won't get a speeding ticket on HWY 395".  Guess what he said when he pulled me over on 395 and gave me a speeding ticket?  He said "Do you know you were going almost 80?"

 

I was able to comply when the ceiling was 10,000' absolute, I find it funny that it isn't feasible to comply with the less restrictive rule with the 2,000' AGL exception.

 

The biggest problem with compliance as written isn't climbing and descending or going around.  The biggest problem is targeting a small window to cross a ridge or pass only to find that the area has a rotor or other lee side issues and you then have to declare and emergency to get your ass out of the area ASAP without regard to altitude limitations.  Its really dumb to get sucked into that in an attempt to comply.

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