VFR On Top

VFR is Visual Flight Rules. What the on top is I don't know unless that means it's your primary means of flying.

The following defination is from the American Meteorological Society glossary:

VFR on top—A flight condition wherein an aircraft is operated under modified visual flight rules while in flight above a layer of clouds and/or an obscuring phenomenon sufficient to constitute a ceiling.
The limiting conditions for flying “VFR on top” are prescribed in Civil Air Regulations. Compare VFR between layers.

For additional definations

[url]http://www.amsglossary.allenpress.com/ glossary[/url]

The problem with VFR on top is when you have to come back down for a landing

I was flying VFR PANC to PAWR in the sim yesterday with a descent cloud layer. I decided to climb above it to keep the turbulence low (didn't seem that thick at first), but soon i found myslef staring down at nothing but clouds! Not much chance to orient myself there! I finally had to lose about 5000 feet just to get low enough to see the river I was following!

VFR on top is a condition of flight in which you fly in visual conditions but with an underlying cloud layer that obscures the ground. It can be entered from either IFR or VFR flight. In VFR on top, you are subject to the rules of VFR flight-altitude levels, flight course at the pilot's discretion, etc, even if you entered from an IFR flight plan. Approporiately rated and equipped pilots can elect to be in VFR conditions but remain on their IFR flight plan or they can advise ATC that they are transitioning to VFR on top rules.

Pilots can fly VFR on top even if they are not instrument rated (in the US-I don't know what the rules are for other countries). However, it's a bit more risky if you are not rated. If the undercast does not end when expected or if you encounter an emergency that requires descent while still above the undercast, you are in a much more dangerous situation than IFR rated pilots.

When I was in training in the San Diego area, I would often fly VFR on top on flights up and down the coast line since the marine layer southern California often has, usually extends only a few miles inland. If I had a problem, I could turn east and fly out of the "on top" conditions within a few minutes.

Don Wood wrote:

VFR on top is a condition of flight in which you fly in visual conditions but with an underlying cloud layer that obscures the ground. It can be entered from either IFR or VFR flight. In VFR on top, you are subject to the rules of VFR flight-altitude levels, flight course at the pilot's discretion, etc, even if you entered from an IFR flight plan. Approporiately rated and equipped pilots can elect to be in VFR conditions but remain on their IFR flight plan or they can advise ATC that they are transitioning to VFR on top rules.

Pilots can fly VFR on top even if they are not instrument rated (in the US-I don't know what the rules are for other countries). However, it's a bit more risky if you are not rated. If the undercast does not end when expected or if you encounter an emergency that requires descent while still above the undercast, you are in a much more dangerous situation than IFR rated pilots.

When I was in training in the San Diego area, I would often fly VFR on top on flights up and down the coast line since the marine layer southern California often has, usually extends only a few miles inland. If I had a problem, I could turn east and fly out of the "on top" conditions within a few minutes.

Ok, thanks. Is there an altitude requirement, like you can't go above 18,000 msl?

Yes, there is an 18,000 foot ASL altitude restriction for VFR (on top or otherwise). 18,000 feet is the floor of Positive Control Airspace and all traffic in PCA must be on an IFR flight plan.