Recommendation Date
Recipient Name
CAA
Text
Ensure that waivers of the wake turbulence separation standards are: (i) restricted to VMC, by day only; and (ii) specifically acknowledged by pilots with words such as "ACCEPT WAIVER"; and (iii) not permitted under certain circumstances, for example:
when a light aircraft:
(a) will take-off behind a heavy or medium aircraft from a point on the runway more than 150 m beyond where the heavy or medium aircraft started its take-off roll; or
(b) will take-off in the opposite direction to a heavy or medium aircraft that has just taken-off from, or carried out a missed approach to, the same runway; or
when a medium aircraft:
(c) will take-off behind a heavy aircraft from a point on the runway more than 150 m beyond where the heavy aircraft started its take-off roll; or
(d) will take-off in the opposite direction to a heavy aircraft that has just taken-off from, or carried out a missed approach to, the same runway. (This is similar to the Australian restrictions on granting waivers.)
when a light aircraft:
(a) will take-off behind a heavy or medium aircraft from a point on the runway more than 150 m beyond where the heavy or medium aircraft started its take-off roll; or
(b) will take-off in the opposite direction to a heavy or medium aircraft that has just taken-off from, or carried out a missed approach to, the same runway; or
when a medium aircraft:
(c) will take-off behind a heavy aircraft from a point on the runway more than 150 m beyond where the heavy aircraft started its take-off roll; or
(d) will take-off in the opposite direction to a heavy aircraft that has just taken-off from, or carried out a missed approach to, the same runway. (This is similar to the Australian restrictions on granting waivers.)
Reply Text
The first two points of the recommendation are adopted to the extent that the proposals will be forwarded to the Assistant Director Rules and Standards for processing as a petition for rulemaking as an amendment to the appropriate Rule or Advisory Circular, probably Part 91 or its associated ACs.
The third point is not adopted on the basis that:
• it does not impose any specific requirements on any person. It would be inappropriate to place the responsibility for determination of what was safe and what was not on the air traffic controller. Such persons would be unlikely to have sufficient knowledge to carry out such a function;
• it is too specific in quoting distances which may be appropriate on some occasions and inappropriate on others; and
• the ultimate responsibility for the safe operation of the aircraft rests upon the pilot-in-command.
The third point is not adopted on the basis that:
• it does not impose any specific requirements on any person. It would be inappropriate to place the responsibility for determination of what was safe and what was not on the air traffic controller. Such persons would be unlikely to have sufficient knowledge to carry out such a function;
• it is too specific in quoting distances which may be appropriate on some occasions and inappropriate on others; and
• the ultimate responsibility for the safe operation of the aircraft rests upon the pilot-in-command.
Related Investigation(s)