Is a takeoff alternate required?
Thread Starter
Join Date: Jul 2003
Location: dublin/ireland
Posts: 71
Likes: 0
Received 0 Likes
on
0 Posts
Is a takeoff alternate required?
Hi All
Quick question that I want to get clear in my head as I have heard and read many opinions on it..
If I am departing in low vis conditions from a runway that is CAT3A approved , do I need the weather conditions to be CAT3A or above or CAT1 or above when deciding if a takeoff alternate is required??
Thanks
Topgun
Quick question that I want to get clear in my head as I have heard and read many opinions on it..
If I am departing in low vis conditions from a runway that is CAT3A approved , do I need the weather conditions to be CAT3A or above or CAT1 or above when deciding if a takeoff alternate is required??
Thanks
Topgun
Join Date: Nov 1999
Posts: 2,312
Likes: 0
Received 0 Likes
on
0 Posts
Depends if you can return to the departure airfield having taken into account the meteorological and/or performance considerations.
If an aircraft can commence an approach to the airfield in Cat 3A conditions after the loss of an engine then in theory that would preclude the absolute need for a take off alternate to be specified. If not, then one must be nominated and it would need to be above the applicable landing minima taking the same performance considerations into account, as well as the other applicable terrain and distance requirements. Obviously that wouldn't be the wisest course of action, but that is the requirement.
If an aircraft can commence an approach to the airfield in Cat 3A conditions after the loss of an engine then in theory that would preclude the absolute need for a take off alternate to be specified. If not, then one must be nominated and it would need to be above the applicable landing minima taking the same performance considerations into account, as well as the other applicable terrain and distance requirements. Obviously that wouldn't be the wisest course of action, but that is the requirement.
Join Date: Apr 2007
Location: USA
Posts: 42
Likes: 0
Received 0 Likes
on
0 Posts
Assuming we are talking about US operations conducted under CFR 121, where is the requirement to take into account single engine landing minima? The regulation CFR 121.617, only references "landing minimums", not single engine landing minimums.
Join Date: Mar 2008
Location: UK
Posts: 329
Likes: 0
Received 0 Likes
on
0 Posts
The poster's from Europe so I'd suggest they're after JAA requirements.
My company/aircraft don't allow for planning a single-engine landing in conditions less than Cat 1. That said, if we have an engine failure at a certain point during an LVP approach we're allowed to continue to landing i.e. the aircraft's capable. If the conditions are below Cat 1 at the departure airfield i.e. precluding a single-engine return, we nominate a Cat I takeoff alternate (within 400 nm or one hour's single-engine, still air, flying time, whichever the more limiting).
B&S
My company/aircraft don't allow for planning a single-engine landing in conditions less than Cat 1. That said, if we have an engine failure at a certain point during an LVP approach we're allowed to continue to landing i.e. the aircraft's capable. If the conditions are below Cat 1 at the departure airfield i.e. precluding a single-engine return, we nominate a Cat I takeoff alternate (within 400 nm or one hour's single-engine, still air, flying time, whichever the more limiting).
B&S
Think of it this way... What would happen if, after take-off and no alternate nominated, you had a failure or series of failures which downgraded your aircraft to CAT 1 only?
I reckon Beazlebub has summed it up pretty correctly, be it FAA or JAA.
If you can get back into your departure airfield, using normal operating minima, performance allowing, and taking any additional single engined restrictions into account, then you do not need a take-off alternate. So under JAA rules if you are flying a twin that is CAT3A capable "on one" and you have CAT 3A conditions at your departure airport you do not need a take off alternate, all IMHO of course
.
If you can get back into your departure airfield, using normal operating minima, performance allowing, and taking any additional single engined restrictions into account, then you do not need a take-off alternate. So under JAA rules if you are flying a twin that is CAT3A capable "on one" and you have CAT 3A conditions at your departure airport you do not need a take off alternate, all IMHO of course
.
Join Date: Apr 2007
Location: USA
Posts: 42
Likes: 0
Received 0 Likes
on
0 Posts
I don't want to be argumentative, as this is an academic question at this point. Is there a regulatory source or reference that supports the position that the landing minimums need to be referenced to the single engine capability as opposed to whatever all engine landing minimums are approved via op's specs.
I understand the safety implications, but as an academic question, is using single engine capabilities required, and if so where is the requirement?
I understand the safety implications, but as an academic question, is using single engine capabilities required, and if so where is the requirement?
Join Date: Mar 2008
Location: Above the Transition Level
Posts: 160
Likes: 0
Received 0 Likes
on
0 Posts
The reference is JAROPS 1.295 for met reasons discussed but also performance should be considered eg. is the runway long enough with 1 reverser etc.
Obviously company SOPS may be more restrictive though.
Obviously company SOPS may be more restrictive though.
Join Date: Mar 2008
Location: UK
Posts: 329
Likes: 0
Received 0 Likes
on
0 Posts
The regs mention met or perf reasons, which is obviously a pretty broad brush and will affect different operators/aircraft in different ways...
EU-OPS 1.295:-
EU-OPS 1.295:-
(b) An operator must select and specify in the operational flight plan a take-off alternate aerodrome if it would not be possible
to return to the departure aerodrome for meteorological or performance reasons. The take-off alternate aerodrome,
in relation to the departure aerodrome, shall be located within:
1. for two-engined aeroplanes, either:
(i) one hour flight time at a one-engine-inoperative cruising speed according to the Aircraft Flight Manual (AFM)
in still air standard conditions based on the actual take-off mass; or
(ii) the operator’s approved ETOPS diversion time, subject to any MEL restriction, up to a maximum of two
hours, at the one-engine-inoperative cruising speed according to the AFM in still air standard conditions
based on the actual take-off mass for aeroplanes and crews authorised for ETOPS;
to return to the departure aerodrome for meteorological or performance reasons. The take-off alternate aerodrome,
in relation to the departure aerodrome, shall be located within:
1. for two-engined aeroplanes, either:
(i) one hour flight time at a one-engine-inoperative cruising speed according to the Aircraft Flight Manual (AFM)
in still air standard conditions based on the actual take-off mass; or
(ii) the operator’s approved ETOPS diversion time, subject to any MEL restriction, up to a maximum of two
hours, at the one-engine-inoperative cruising speed according to the AFM in still air standard conditions
based on the actual take-off mass for aeroplanes and crews authorised for ETOPS;
