At what minimum altitude crossing the Atlantic Must I file IFR?
18,000 feet MSL
When the prescribed minimum altitude for IFR operations is at or above 18,000 feet MSL and the atmospheric pressure is less than 29.92”, add the appropriate adjustment factor from TBL 4-5-3 to the flight level equivalent of the minimum altitude in feet to determine the adjusted minimum flight level.
What is the minimum safe altitude anywhere over congested areas?
1,000 feet
91.119 Minimum safe altitudes; general (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.
Are You required to report leaving an altitude?
To the first question: no, you are not required to report leaving any altitude. Those items that must be reported are listed in 14 CFR 91.183, including:
What are the altitude assignment and verification rules?
Altitude Assignment and Verification Separate instrument flight rules ( IFR) aircraft using the following minima between altitudes: Up to and including FL 410- 1,000 feet. Apply 2,000 feet at or above FL 290 between non-RVSM aircraft and all other aircraft at or above FL 290.
Do you have to report Your Leaving level?
In the US… Under radar contact the leaving level phraseology is not expected nor needed by ATC. What they do need is you tell them what altitude you are at (plus climbing/descend to) when you check in. The leaving level is mandatory when flying without radar contact.
Do you have to report leaving an ATC?
ATC will protect all altitudes between your current one and the restriction, and you are free to hit that restriction as you see fit (barring the violation of other regulations, of course). You may not return to a previously vacated altitude as part of your climb/descent, but you may level.