I just heard this on liveatc and watched it here on FA.
Here is the situation:
You are the PIC of a large (~30 seat) regional turboprop operating on a scheduled flight. You check in with the tower while doing an ILS to runway 11 approach. The tower advises “new weather is 400 overcast visibility 3 miles wind 300 at 14 knots, temperature 13 dew point 12, altimeter 29.98.” Minimums for a straight in approach are 200 ft., 1/2 mile, circling are 1100 ft., 3 miles. You request two additional updates on the weather while on final with no appreciable changes. You make a missed approach, when and why?
The weather reported was accurate. The runway is 6100 feet long, near sea level. All components operating normally.
bonus question: The Cessna 208 behind you lands. was he legal?
Aspiring commercial, or low time comm. pilots only.
The tailwind/available runway length combination is unacceptable to the large turboprop, and the ceiling is below circling minimums. C208 is ok with the tailwind/available runway length.
Nice one Mark, partly true. Every part 25 airplane I’ve flown has a 10 knot tailwind limit for takeoff or landing. Period. Runway length is of course a consideration but not for this question. Even for the G2 which predates the formation of the FAA.
Where did they make the missed approach? At circling or straight in minimums?
I actually couldn’t tell where these guys missed the approach.
As I see it you have two choices.
Circling minimums, that way you are still in the clouds and don’t have to do some song and dance explanation to the passengers about maximum tailwinds etc.
Or Straight in minimums hoping the wind dies down to 10 knots before you get there.
I can think of no legal reason not to use either choice. Just don’t land if the wind doesn’t die down. Your friendly local fed might be watching.
You might get an argument that making a missed approach with a tailwind from the lowest minimums for that airport would give you a lower than required climb gradient, but I’ve never seen it in writing anywhere.
Of course the 10 knot limit does not apply to smaller aircraft. Only dangerous and reckless operations if you run off the end of the runway!
The kicker is the competition arrived about 15 minutes after these guys went back to LAX and the wind was 290 at 10! They landed.
Actually, if the reported weather is below minimums, I don’t think they can even start the approach. Only Part 91 guys can fly a “lets see what it is when I get to minimums” approach. If the reported tailwind component would require a circling approach and the minimums are below circling minimums, I’m pretty sure you’d have to hold or divert to someplace above minimums.
Good point Tim. It’s been a long time since I flew 135 but as I remember only visibility triggers that restriction. These guys had the circling visibility.
The large aircraft tailwind applies to all operators since it is an aircraft certification limit.
The smoke has been playing havoc on the airline schedules all day in SBP. Been hanging around 2 1/2 to 4 miles all day. It looks like several of the airlines don’t have GPS approval and they also have an ops spec requiring 3 miles visibility to circle. There have been at least two diversions and several had to hold for a few minutes but ended up getting lucky before diverting.
Yep, I stand corrected. It’s only the visibility reported at the start of the approach that determines whether or not you can start the approach. Now, if you’re on the approach, established and stabilized, and the reported visibility drops below the minimums, can you continue the approach?
Are you sure that’s not in the ops manual for the airline? I know that the a/c I fly and am familiar with only have a maximum demonstrated crosswind component. That’s only a certification requirement, i.e. it has to be shown to be landable at a crosswind thats some fraction of the Vs0 or somesuch. The aircraft may in fact be able to handle a much higher crosswind.
Then again, I’m not intimately familiar with the POHs for large a/c either, hence my question.
I’ll be sure to read up some literature so I can make a better guess next time!
