If weather is below landing MIN at the departure airport, T/O ALT must be added within:
400 NM
When is a second destination ALT required
If destination and first ALT are both marginal
What is the 1-2-3 ALT rule
An ALT is required if forecast weather at destination is:
+/- 1 hour of ETA is less than 2000’ ceilings or 3 sm visibility. Conditional terms such as TEMPO OR PROB will also require an ALT.
What is the 1-1-3 ALT rule
Within the lower 48 states or returning from extended domestic operation an ALT is required if forecast weather is: +/- 1 hour of ETA is less than 1000’ ceilings or 3 sm visibility. CAT 1 runway must be legal and available.
What is the 1-1-2 ALT rule
Within the lower 48 states or returning from extended domestic operation an ALT is required if forecast weather is: +/- 1 hour of ETA is less than 1000’ ceilings or 2 sm visibility. CAT II/III runway must be legal and available.
When is using the 1-1-3 or the 1-1-2 rule not an option
When TEMP OR PROB is in the forecast
If a listed ALT is going to be below minimums at the time a flight would arrive, can it be changed?
Yes with Dispatch concurrence to amend the release.
What if an ALT is no longer required?
Captain and Dispatcher may agree to amend the release and delete the ALT. ALT fuel will then become extra fuel.
In addition to regulatory requirements, ALT will be added for the following reasons:
Crosswind: An alternate will be designated whenever crosswind performance guidelines may prevent a safe landing.
Unlighted Airport: A flight scheduled to land at an unlighted airport 30 min before sunset and must have a lighted ALT.
Enroute Alternates (Engine Out Drift Down) requirements
Same as destination ALT requirements
Can a No Tower Airport be used as an ALT
Yes as long as the Approach Plate does not prohibit its use as an ALT. The navaid is monitored.
Determining Alternate Weather Minimums for an airport with just one operational approach facility
For airports with one operational approach facility:
Determining Alternate Weather Minimums for an airport with two operational approach facilities to different runways
Use the lowest value obtained from each.
Determining Alternate Weather Minimums for airports with CAT II/III approach and at least two operational ILS facilities serving different runways
Take Off Weight Increase that requires contacting Dispatch
+2000lb
First Officer Takeoff Minimums
TDZ and rollout RVR 1000’ or greater
First Officer Landing Minimums
Landing visibility equal to or greater than 1800 RVR or 1/2 mile
Circling Approach Minimums
1000’ ceiling and 3 miles visibility or published which is ever higher
Raw Data ILS
4000’ RVR or 3/4 mile visibility
Visual Approach Minimums
1000’ ceiling and 3 miles visibility
Stabilized Approach Limits by 1500’ AGL or FAF
- Airspeed less than or equal to 180kts
Stabilized Approach Limits by 1000’ AGL
Stabilized Approach Limits by 500’ AGL
Holding Speed from Surface to 6000’
200 kts max 1 min.