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This question is a bit specific because it applies to an actual situation I'm observing for a flight I'm looking to make tomorrow.

I'm a Non-IFR rated pilot looking to fly class D airspace. My destination airport is anticipated to have clouds (FEW @ 1,000 ft). In this case, it seems like it would be pretty easy for 1 single cloud's position to make it impossible for me to land at the airport despite being able to (likely) safely land. For example, if the cloud were over the middle of the runway, but I had plenty of runway at my landing end, it's technically possible that the requirements for distance from clouds could keep me from landing here.

enter image description here

I realize the example is trite, but hopefully this illustrates my point.

  1. What is the appropriate way to handle this situation as a pilot?
  2. I'm calling up tower before I have a visual on the airport (which would be the case in this situation) would they likely deny clearance to land due to knowing that a singular cloud sits out there and would cause a bust the visual flight rules or might they clear me without regard to the rules?
  3. What is considered cloud clearance in this situation? I realize clearance is easy to determine if you are directly above, below or adjacent to a cloud, but more commonly you'll be at some sort of angle to the cloud as in the picture. Shown are two ways to consider cloud clearance (in red and blue lines)
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    $\begingroup$ As for #2, no. It's up to you to stay the required distance from clouds. There's no way we can see from the tower how far you are from a certain cloud, and even if we could we really have better things to do. $\endgroup$ – J. Hougaard Jul 28 '17 at 21:24
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  1. What is the appropriate way to handle this situation as a pilot?

First, tell tower about the problem. They may be able to assign you a different runway, have you loiter (circle) for a minute or three, etc. It's likely not the first time this has ever happened.

If necessary ask the tower for a Special VFR clearance. That changes your cloud clearance requirements dramatically in your favor. Note that the tower is not allowed to offer this clearance to you - you have to explicitly ask for it.

  1. I'm calling up tower before I have a visual on the airport (which would be the case in this situation) would they likely deny clearance to land due to knowing that a singular cloud sits out there and would cause a bust the visual flight rules or might they clear me without regard to the rules?

J. Hougaard answered this part in the comments - the tower is likely not checking how far you are from a single cloud.

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    $\begingroup$ Good point on the SVFR, that makes this situation much more reasonable. $\endgroup$ – Ryan Griffith Jul 28 '17 at 21:55
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  1. I agree that SVFR is easiest way to deal with this situation. However, sometimes controllers resist going through trouble of SVFR when its just one or two puffy clouds in the pattern and the reported weather is VFR.

  2. They don't care about one cloud. Its not their responsibility for you keeping your cloud clearances. Especially when weather is reported as VFR. You need to maneuver around or under the cloud for landing. Another regulation is the minimum safe altitude regulation, but it has an exception for landings and takeoff. So if you need to deviate from traffic pattern altitude to maintain cloud clearances by going under or around the cloud, tell the tower what you are doing.

(Scenario: There is a cloud at 1200 on downwind leg. Traffic pattern altitude is 1000. You see the cloud, and you estimate you need to be at 700 feet to maintain cloud distance. You tell the tower what you are doing and do it, then proceed with landing. Alternatively, if you're cleared to land, just start your decent a little earlier on downwind to 700, maintain that altitude until you're ready to finish the approach.)

  1. This is a good question. Cloud distances are given in horizontal and vertical (above or below) distances, not in diagonal. The square box in your diagram calculates the distances as described in the minimum safe altitudes section 91.119 over populated areas where it states "1000 feet above the highest obstacle within a horizontal radius of 2000 feet." However, the distance in the Basic VFR weather minimums section 91.155 do not use that same description. No where in 91.155 does it talk about keeping 500 feet below a horizontal distance from a 2000 ft radius of a cloud, or any similar language. Therefore, I think the dotted rectangle in your diagram is overly (conservative) and not supported by the language of the section 91.155.

NOTE: the other dotted line in your diagram is also incorrect because it doesn't capture the 500 ft directly below the edges of the cloud.

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