Instrument Quiz

FlyChicaga · June 30th, 2004, 09:11

This question came up the other day at work.

You are schedule to depart at 16:05Z. You're arrival time is scheduled as 16:55Z. Here is the TAF and METAR for the departure and destination airports that comes with your release.

KMDW 301453Z 26004KT 5SM BKN035 25/13 A2999 RMK AO2 SLP201 T02500133 50000

KMDW 301120Z 301212 23005KT 4SM BKN040
FM1600 22008KT 3SM BKN020 TEMPO 1718 4SM BKN030
FM1900 VRB04KT P6SM BKN070
FM0100 23004KT P6SM SKC

KGRR 301456Z 24009KT 10SM CLR 24/16 A3014 RMK AO2 SLP203 T02440156 50002

KGRR 301120Z 301212 23007KT P6SM SCT070
FM2000 26012G18KT P6SM SCT050
FM0100 22005KT P6SM SKC

Remembering the 1-2-3 rule for filing an alternate, would you need an alternate for this flight? You are departing KGRR, and arriving KMDW. Again, departure at 16:05Z, arrival at 16:55Z.

cime_sp · June 30th, 2004, 09:41

The answer is no you do not need an alternate. The FAR's say that the weather must be "atleast" 2,000' and 3sm visablity from 1 hour before to 1 hour after. You only need an alternate if weather is forecast BELOW those minimums.

RiddlePilot · June 30th, 2004, 13:46

[ QUOTE ]
The answer is no you do not need an alternate. The FAR's say that the weather must be "atleast" 2,000' and 3sm visablity from 1 hour before to 1 hour after. You only need an alternate if weather is forecast BELOW those minimums.

[/ QUOTE ]

Agreed.

kellwolf · June 30th, 2004, 22:54

Gotta agree with the above posts. Wording is "at least" so you are right AT the minimums. Question is, what are your company and 121 alternate minimums?

mtsu_av8er · July 1st, 2004, 00:01

[ QUOTE ]
Gotta agree with the above posts. Wording is "at least" so you are right AT the minimums. Question is, what are your company and 121 alternate minimums?

[/ QUOTE ]

Ohh, I know 121 minimums!!

Wait, not fair...

FlyChicaga · July 1st, 2004, 08:07

[ QUOTE ]
Gotta agree with the above posts. Wording is "at least" so you are right AT the minimums. Question is, what are your company and 121 alternate minimums?

[/ QUOTE ]

The wording is the same in our manuals. "At least." There is a whole mess of things regarding alternate minimums under 121, but for filing an alternate the 1-2-3 rule still applies. When it comes to the weather minimums for the alternate, second alternate, exemption 3585, etc., it's a whole new bag of tricks. We don't always use the 600-2 or 800-2 minimums from Part 91. If you want more detail I'll expand, but tired now...

aloft · July 1st, 2004, 21:29

Why does he "barely" meet the minimums? The worst wx forecast, 3 hrs after his arrival, is SCT050--not a ceiling, still VFR. Am I missing something?

kellwolf · July 1st, 2004, 23:45

That's the departure aiport. The weather reports are kinda reversed. The flight leaves GRR and arrives MDW.

aloft · July 2nd, 2004, 19:21

Ahso...yup, missed that little detail!

So the forecast for 1 hr prior to arrival is the magic min of 2000 and 3 SM, improving to 3000' and 4 SM in the hour after arrival. So no, no alternate required.

JAM · July 4th, 2004, 10:31

[ QUOTE ]
This question came up the other day at work.

You are schedule to depart at 16:05Z. You're arrival time is scheduled as 16:55Z. Here is the TAF and METAR for the departure and destination airports that comes with your release.

KMDW 301453Z 26004KT 5SM BKN035 25/13 A2999 RMK AO2 SLP201 T02500133 50000

KMDW 301120Z 301212 23005KT 4SM BKN040
FM1600 22008KT 3SM BKN020 TEMPO 1718 4SM BKN030
FM1900 VRB04KT P6SM BKN070
FM0100 23004KT P6SM SKC

KGRR 301456Z 24009KT 10SM CLR 24/16 A3014 RMK AO2 SLP203 T02440156 50002

KGRR 301120Z 301212 23007KT P6SM SCT070
FM2000 26012G18KT P6SM SCT050
FM0100 22005KT P6SM SKC

Remembering the 1-2-3 rule for filing an alternate, would you need an alternate for this flight? You are departing KGRR, and arriving KMDW. Again, departure at 16:05Z, arrival at 16:55Z.

[/ QUOTE ]

I must be missing something here. This seems pretty clear. No alternate needed. 121 alternate mins do not apply when no alternate is needed.

June 30th, 2004, 09:11	#1
FlyChicaga Old Skool Join Date: Dec 2001 Location: Chicago, IL Posts: 4,833	Instrument Quiz This question came up the other day at work. You are schedule to depart at 16:05Z. You're arrival time is scheduled as 16:55Z. Here is the TAF and METAR for the departure and destination airports that comes with your release. KMDW 301453Z 26004KT 5SM BKN035 25/13 A2999 RMK AO2 SLP201 T02500133 50000 KMDW 301120Z 301212 23005KT 4SM BKN040 FM1600 22008KT 3SM BKN020 TEMPO 1718 4SM BKN030 FM1900 VRB04KT P6SM BKN070 FM0100 23004KT P6SM SKC KGRR 301456Z 24009KT 10SM CLR 24/16 A3014 RMK AO2 SLP203 T02440156 50002 KGRR 301120Z 301212 23007KT P6SM SCT070 FM2000 26012G18KT P6SM SCT050 FM0100 22005KT P6SM SKC Remembering the 1-2-3 rule for filing an alternate, would you need an alternate for this flight? You are departing KGRR, and arriving KMDW. Again, departure at 16:05Z, arrival at 16:55Z.

June 30th, 2004, 09:41	#2
cime_sp Senior Member Join Date: Oct 2002 Location: ATL Posts: 782	Re: Instrument Quiz The answer is no you do not need an alternate. The FAR's say that the weather must be "atleast" 2,000' and 3sm visablity from 1 hour before to 1 hour after. You only need an alternate if weather is forecast BELOW those minimums.

June 30th, 2004, 13:46	#3
RiddlePilot Senior Member Join Date: Apr 2003 Location: Prescott, AZ Posts: 928	Re: Instrument Quiz [ QUOTE ] The answer is no you do not need an alternate. The FAR's say that the weather must be "atleast" 2,000' and 3sm visablity from 1 hour before to 1 hour after. You only need an alternate if weather is forecast BELOW those minimums. [/ QUOTE ] Agreed.

June 30th, 2004, 22:54	#4
kellwolf Old Skool Join Date: Jun 2003 Location: Memphis, TN Posts: 13,860	Re: Instrument Quiz Gotta agree with the above posts. Wording is "at least" so you are right AT the minimums. Question is, what are your company and 121 alternate minimums?

July 1st, 2004, 00:01	#5
mtsu_av8er Old Skool Join Date: Dec 2002 Location: Utopia Posts: 12,567	Re: Instrument Quiz [ QUOTE ] Gotta agree with the above posts. Wording is "at least" so you are right AT the minimums. Question is, what are your company and 121 alternate minimums? [/ QUOTE ] Ohh, I know 121 minimums!! Wait, not fair...

July 1st, 2004, 08:07	#6
FlyChicaga Old Skool Join Date: Dec 2001 Location: Chicago, IL Posts: 4,833	Re: Instrument Quiz [ QUOTE ] Gotta agree with the above posts. Wording is "at least" so you are right AT the minimums. Question is, what are your company and 121 alternate minimums? [/ QUOTE ] The wording is the same in our manuals. "At least." There is a whole mess of things regarding alternate minimums under 121, but for filing an alternate the 1-2-3 rule still applies. When it comes to the weather minimums for the alternate, second alternate, exemption 3585, etc., it's a whole new bag of tricks. We don't always use the 600-2 or 800-2 minimums from Part 91. If you want more detail I'll expand, but tired now...

July 1st, 2004, 21:29	#7
aloft Old Skool Join Date: Sep 2001 Location: Inside your OODA loop Posts: 7,009	Re: Instrument Quiz Why does he "barely" meet the minimums? The worst wx forecast, 3 hrs after his arrival, is SCT050--not a ceiling, still VFR. Am I missing something?

July 1st, 2004, 23:45	#8
kellwolf Old Skool Join Date: Jun 2003 Location: Memphis, TN Posts: 13,860	Re: Instrument Quiz That's the departure aiport. The weather reports are kinda reversed. The flight leaves GRR and arrives MDW.

July 2nd, 2004, 19:21	#9
aloft Old Skool Join Date: Sep 2001 Location: Inside your OODA loop Posts: 7,009	Re: Instrument Quiz Ahso...yup, missed that little detail! So the forecast for 1 hr prior to arrival is the magic min of 2000 and 3 SM, improving to 3000' and 4 SM in the hour after arrival. So no, no alternate required.

July 4th, 2004, 10:31	#10
JAM Junior Member Join Date: Oct 2002 Location: Florida Posts: 246	Re: Instrument Quiz [ QUOTE ] This question came up the other day at work. You are schedule to depart at 16:05Z. You're arrival time is scheduled as 16:55Z. Here is the TAF and METAR for the departure and destination airports that comes with your release. KMDW 301453Z 26004KT 5SM BKN035 25/13 A2999 RMK AO2 SLP201 T02500133 50000 KMDW 301120Z 301212 23005KT 4SM BKN040 FM1600 22008KT 3SM BKN020 TEMPO 1718 4SM BKN030 FM1900 VRB04KT P6SM BKN070 FM0100 23004KT P6SM SKC KGRR 301456Z 24009KT 10SM CLR 24/16 A3014 RMK AO2 SLP203 T02440156 50002 KGRR 301120Z 301212 23007KT P6SM SCT070 FM2000 26012G18KT P6SM SCT050 FM0100 22005KT P6SM SKC Remembering the 1-2-3 rule for filing an alternate, would you need an alternate for this flight? You are departing KGRR, and arriving KMDW. Again, departure at 16:05Z, arrival at 16:55Z. [/ QUOTE ] I must be missing something here. This seems pretty clear. No alternate needed. 121 alternate mins do not apply when no alternate is needed.

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