IFR flight planning minimum

[kevinsky18]

I'm not an IFR guy. But I have an IFR question in regards to weather that I need answered.

First I did do a search and for some weird reason the search function doesn't kick back hits for "IFR." Weird of course becuase there is plenty of topics. Now to my question.

What are the weather minimums for flight planning an IFR trip. I know where to find the minimums for approach i.e. on the approach plates. That's not my question.

My question is. If I'm going to an airport and the minimums are 400 feet and 1/2 mile. What can the weather be when I leave my departure airport?

In other words. Can I leave on an IFR flight if the weather is:
A: At or below the reported minimums at my destination.
B: Forcast to be below the minimums when I arrive.
C: what happens if the weather is fluctating above and below the minimums both at the time of departure and at my proposed arrival time.
D: what if there is no forecast. What if the there is only an observation and a Area Forcast but not aerodrome forecast?

I'm looking for the actual CARs regs. I tried to find this detail within CARs but no luck.

I have a vague recollection of looking this up years ago and I remember the answer being more restrictive than I imagined. something like above minimums for an hour before and forcasted for an hour after. But my memory is bad and I could be remember wrong.

Your help would be appreciated.

[FlaplessDork]

The CAP GEN is incorporated by reference in the CARs. Therefore the CAP GEN is a legal document. Read the CAP GEN. I believe its just the Alternate Minimums determine whether you can leave or not on a private flight. Nothing says you can't leave and give it a try to see if your destination is better than forecast or reported, but your alternate has to meet alternate requirements. All you have to see is the required runway references, but plan for the Missed to your alternate. But, the Approach Ban does apply.

I might be wrong, but I didn't want to look it up. Sometimes its better to wait on the ground for better weather anyway.

[Donald]

Sounds like you have VFR OTT and IFR a little mixed up.

[Rockie]

You can depart for a destination if the weather is 0/0 and forecast to stay that way. But you need an alternate, and the weather requirements for that are well spelled out in the CAR's

[Tim]

to be legal, you go by the TAF (or other forcast) at the time of arrival. although if things are much worse than forecast common sense might say not to use it.

if the weather is fluctuating (i.e. tempo, bcmg, prob) you go with the worst weather for the entire period the bad wx is forecast. so if its good tempo'ed bad you have to use the bad weather for the entire tempo period. if its bad tempo'ed good you still have to use the bad weather. the weather at your departure time does not matter, just arrival.

if there is no TAF, you can use a different set of mins based on the other types of forecasts.

as FD said you can find all the info in the CAP GEN, also it's in the CARs and AIM

[navajo]

My guess is that you are only limited by the forecast weather when you choose your alternate, not your destination, at least with IFR flights.

[kevinsky18]

This would be for a commercial flight.

Hmmm well a few apposing opinions. I've looked again and can't find the exact regs so that I can get actual facts.

I'll look again in the morning when I’m better rested. It’s been a long day.

[BTD]

There are no requirements for destination. As Rockie said, it could be 0/0. Only for alternates. Both for private and commercial ops.

BTD

[altiplano]

+1 on Rockie and BTD...

As long as you hold an alternate it doesn't matter what your destination is doing.

One could argue that if severe icing was forecast/observed at your destination/enroute you wouldn't be legal to go... and I wouldn't want to go... but I don't think that's the info that you are looking for...

[fougapilot]

+1 on Rockie, BTD and Altiplano

The wx at destination is not a real factor in the decision to commence a flight. As long as you have a legal alternate and the takeoff minimums, you can go. 100% legal. Now, this being said, there is much more involved with the go/no go decision. The biggest one might be; Who pays? Whether it is a private or commercial flight, someone pays for this airplane to fly. They should be made aware of the chances to actually land at their desired destination and if they feel it is not worth their money, they could choose not to depart. This way, it avoids difficulties when the time comes to get paid.

I AM NOT ADVOCATING THAT YOU INVOLVE THE CLIENT IN EVERY DECISIONS, simply saying that once YOUR mind is made and SAFETY is NOT a concern, you might want to include the person who pays to fly from point A to point B so he/she accepts the fact that he/she might end up at point C.

As far as the landing at destination is concerned; the decision to land is very hard to dispute. It is a decision made by an individual (or crew in multi-crew airplane) that is made in a very specific point in space and time (and no, I'm not a Treckie). Facts are simple, only the weather at the precise moment the pilot/crew looks out the window is involved in the landing/go around decision. Not the weather 2 seconds prior, not the weather 5 seconds later. When the weather is really bad, it is not unusual to see 1 out of 2 airplane land while the other goes around. This doesn't mean that 1 out of 2 pilot/crew "busts" minimum, it only means that 1 out of 2 pilot/crew saw the required visual references while the other didn't.

My 2cents,

F