life rafts/atpl exam prep

[AirCanuck]

going through the CARS/aerocourse book and doing some memorization as I cram for these evil exams.

Anyone know the logic behind this? I always do better actually understanding than just memorizing... why is 200NM not ok but 400NM is?

[PilotDAR]

My guess would be that to some degree, those values are arbitrary, based upon "feeling okay" about the chances. I expect that the difference between "multi engined" and "transport category" has to do with the more rigorous certification basis of at a transport category aircraft - fewer failures, with less severity, so take a bigger chance with it.

[AirCanuck]

makes sense. I know in the end i just have to memorize it anyway but what helps it stick for me is understanding!

How about this one:

from the CARS:
"Approach Bans — CAT II and CAT III Precision
700.11 No pilot-in-command of an IFR aircraft operated under this Part who is conducting a CAT II or CAT III precision approach shall continue the approach beyond the FAF inbound or, where there is no FAF, the point where the final approach course is intercepted, unless the RVR is equal to or greater than the minimum RVR specified in the Canada Air Pilot in respect of the runway or surface of intended approach for the instrument approach procedure conducted."

in the AIM section on this, it then shows an approach ban chart specifying:
CAT II
RVR A & B: 1200/600

CAT III
RVR A, B & C: 600/600/600

are these the minimum RVR in the CAP referred to? Or is it the advisory vis/RVR for the approach they are referring to?

[co-joe]

going through the CARS/aerocourse book and doing some memorization as I cram for these evil exams.

Anyone know the logic behind this? I always do better actually understanding than just memorizing... why is 200NM not ok but 400NM is?

The main difference is "multi engine aircraft..." vs "transport category aircraft". There are some huge differenced between the two. Transport category machines aka 705 aircraft would have a type A dispatch system, which means a much higher level of awareness about what they are doing. A dispatch centre is directly responsible for flight following and overseeing of all requirements of the flight.

The multi engine aircraft in question means any joe blow with a twin, going from Iqaluit to Nuuk Greenland over the north Atlantic with nothing other than a flight plan.

[photofly]

The multi engine aircraft in question means any joe blow with a twin, going from Iqaluit to Nuuk Greenland over the north Atlantic with nothing other than a flight plan.

Iqaluit to Nuuk is a) the Davis Strait, not the Atlantic, and b) only 350nm over open water, so the guy in the twin would never be more than half that from shore, and (assuming he filed for 175 knots or better) under that rule not need a life raft, either.

edit: that regulation above is incorrectly quoted, and doesn’t make sense. Here’s the actual rule:

“(2) Subject to subsection (3), no person shall operate over water a multi-engined aeroplane that is able to maintain flight with any engine failed at more than 200 nautical miles, or the distance that can be covered in 60 minutes of flight at the cruising speed filed in the flight plan or flight itinerary, whichever distance is the lesser, from a suitable emergency landing site unless life rafts are carried on board and are sufficient in total rated capacity to accommodate all of the persons on board.”

So it’s not 200nm from shore, it’s 200nm (or 60mins at filed cruise) from a suitable emergency landing site, whatever that is. CYFB BGGH is 446nm, and there’s not much to land on in between so maybe your joe does need a raft.

[Eric Janson]

makes sense. I know in the end i just have to memorize it anyway but what helps it stick for me is understanding!

How about this one:

from the CARS:
"Approach Bans — CAT II and CAT III Precision
700.11 No pilot-in-command of an IFR aircraft operated under this Part who is conducting a CAT II or CAT III precision approach shall continue the approach beyond the FAF inbound or, where there is no FAF, the point where the final approach course is intercepted, unless the RVR is equal to or greater than the minimum RVR specified in the Canada Air Pilot in respect of the runway or surface of intended approach for the instrument approach procedure conducted."

in the AIM section on this, it then shows an approach ban chart specifying:
CAT II
RVR A & B: 1200/600

CAT III
RVR A, B & C: 600/600/600

are these the minimum RVR in the CAP referred to? Or is it the advisory vis/RVR for the approach they are referring to?

These are the minimum RVR values - you cannot continue the approach past the point specified if you do not have these values.

[AirCanuck]

makes sense. I know in the end i just have to memorize it anyway but what helps it stick for me is understanding!

How about this one:

from the CARS:
"Approach Bans — CAT II and CAT III Precision
700.11 No pilot-in-command of an IFR aircraft operated under this Part who is conducting a CAT II or CAT III precision approach shall continue the approach beyond the FAF inbound or, where there is no FAF, the point where the final approach course is intercepted, unless the RVR is equal to or greater than the minimum RVR specified in the Canada Air Pilot in respect of the runway or surface of intended approach for the instrument approach procedure conducted."

in the AIM section on this, it then shows an approach ban chart specifying:
CAT II
RVR A & B: 1200/600

CAT III
RVR A, B & C: 600/600/600

are these the minimum RVR in the CAP referred to? Or is it the advisory vis/RVR for the approach they are referring to?

These are the minimum RVR values - you cannot continue the approach past the point specified if you do not have these values.

Yes, so where it says "the minimum RVR specified in the CAP" is that the advisory RVR values for that approach, or is that the approach ban chart RVR? I don't have a CAP on me and live in a rural area. I'm military so we don't use the CAP per se. So the confusion is real.

[co-joe]

The multi engine aircraft in question means any joe blow with a twin, going from Iqaluit to Nuuk Greenland over the north Atlantic with nothing other than a flight plan.

Iqaluit to Nuuk is a) the Davis Strait, not the Atlantic, and b) only 350nm over open water, so the guy in the twin would never be more than half that from shore, and (assuming he filed for 175 knots or better) under that rule not need a life raft, either.

edit: that regulation above is incorrectly quoted, and doesn’t make sense. Here’s the actual rule:

“(2) Subject to subsection (3), no person shall operate over water a multi-engined aeroplane that is able to maintain flight with any engine failed at more than 200 nautical miles, or the distance that can be covered in 60 minutes of flight at the cruising speed filed in the flight plan or flight itinerary, whichever distance is the lesser, from a suitable emergency landing site unless life rafts are carried on board and are sufficient in total rated capacity to accommodate all of the persons on board.”

So it’s not 200nm from shore, it’s 200nm (or 60mins at filed cruise) from a suitable emergency landing site, whatever that is. CYFB BGGH is 446nm, and there’s not much to land on in between so maybe your joe does need a raft.

Good catch. My point was more that an Airline is allowed to get away with a thinner margin for error based to the fact that if they don't make a position reports, people start looking for them right away, whereas light twin guy won't raise any alarms until an hour after ETA, by which time he's been bobbing like a cork in liquid water that's -5C for a few hours already.

[photofly]

I too think light twin guy would be bananas not to carry a life raft!

How do you interpret "suitable emergency landing site"? An airport? A piece of dry flat land? Anywhere dry?