Airline Pilot Forums

Airline Pilot Forums was designed to be a community where working airline pilots can share ideas and information about the aviation field. In the forum you will find information about major and regional airline carriers, career training, interview and job seeker help, finance, and living the airline pilot lifestyle.




View Full Version : Ifr Question...


BEWELCH
10-24-2006, 02:32 PM
When Do We Need A Departure Alternate???


rickair7777
10-24-2006, 04:09 PM
It's depends on whether you're talking 91, 135, or 121.

Ottopilot
10-24-2006, 04:23 PM
The basic rule of thumb is: if you cannot land at your departure airport, you need a takeoff alternate. That's the simple easy short answer. There are longer ones.:D


Puppyz
10-24-2006, 04:49 PM
nice avatar otto, i liked that movie .

multipilot
10-24-2006, 05:44 PM
Part 91 does not require any takeoff mins under IFR. Legally you can take off in zero/zero. There is a line between being legal and common sense. As a good rule of thumb, if the ceiling and visibility are lower than the minimums published in an instrument approach back into your departure airport then it's probably not a good idea to take off right away. 91.175(f)

Part 135 says that you cannot takeoff under IFR from an airport where weather conditions are at or above takeoff minimums but are below authorized IFR landing minimums unless there is an alternate airport within 1 hour's flying time of the departure airport. 135.217

tomgoodman
10-24-2006, 08:12 PM
As I recall, our procedures required a takeoff alternate if the wx was below Cat I, allowing for the loss of an engine. (Single-engine coupled approaches weren't authorized.) That was a "gotcha" on almost every recurrent simulator check. Interestingly, an instructor said that the MD-88 was quite capable of such an approach, but Delta didn't "buy the certification" for it.

kerns bbo
10-25-2006, 03:57 AM
Also remember that if you take off with very poor weather conditions (even 91) and were to say go off the side of the runway you can still get sited under 91.14 (reckless and careless).

rickair7777
10-25-2006, 08:18 AM
Also remember that if you take off with very poor weather conditions (even 91) and were to say go off the side of the runway you can still get sited under 91.14 (reckless and careless).

Stupid and ignorant operation of an airplane is 91.13

mistarose
10-25-2006, 02:21 PM
My CFII checkride is this Friday, no worries. This question came up yesterday when I was flying this approach in a Frasca 242 sim.

Why is there a "3200" and a "3300" listed for the glideslop intercept altitude? Which do you use, and why are their two altitudes listed here? It is the same on the Jeppesen approach plate I was using.

Thanks in advance

Here is the link: http://edj.net/cgi-bin/echoplate.pl?NorthWest/ALW_i_lr20.gif

waflyboy
10-25-2006, 02:53 PM
Why is there a "3200" and a "3300" listed for the glideslop intercept altitude? Which do you use, and why are their two altitudes listed here? It is the same on the Jeppesen approach plate I was using.

Been a while since I've looked at NOS plates (and I don't have the Jepps for WA), but here's what I think: 3300 is the GS intercept altitude, as shown by the lightening bolt. 3200 is the minimum altitude for that segment when not using the GS (as shown by the *LOC only notation).

rickair7777
10-25-2006, 03:05 PM
Been a while since I've looked at NOS plates (and I don't have the Jepps for WA), but here's what I think: 3300 is the GS intercept altitude, as shown by the lightening bolt. 3200 is the minimum altitude for that segment when not using the GS (as shown by the *LOC only notation).

Yup, that's it.

mistarose
10-25-2006, 04:45 PM
That would make sense to me, is that common - I don't believe I have ever seen that notation before. Usually those altitudes are the same value, why would they need to have a a 100 foot difference? If it was a larger value I could come to some sort of conclusion, but 100 feet? Thanks

waflyboy
10-25-2006, 04:53 PM
I've seen it a few times. Not sure why, but my best guess is that perhaps the 3,300' figure doesn't meet descent angle criteria for non-precision approaches.

btwissel
10-27-2006, 07:04 AM
3300' looks like the GS intercept, and 3200 is the MDA before reaching the marker inbound for the LOC only approach

of course i'm too used to my jepp charts too

mistarose
10-27-2006, 07:40 AM
We have all ready determined that to be true, I am now curious WHY they couldn't make the localizer and glideslope intercept altitude the same value?:o