Tee Emm
5th Jul 2009, 04:12
The Boeing 737 FCTM discusses various cross-wind landing techniques suitable to the aircraft. Three main types are mentioned. They are: De-crab in the flare; touchdown with crab (usually by default!) and sideslip technique. One paragraph states "The greater amount of crab at touchdown, the larger the lateral deviation from the point of touchdown. For this reason, touchdown in a crab only condition is not recommended when landing on a dry runway in strong crosswinds." Boeing do not quote figures for "strong" crosswinds - leaving that interpretation to the pilot. Not much help, really.
I have talked to pilots who use the crosswind technique of deliberately not removing drift before touchdown. They argue the FCTM allows that, without damage to the landing gear. That this technique often feels and sounds terrible if touch down is with significant drift, seems not to faze them. Is it because they are tense when faced with crosswinds? Or, because they have not been properly trained and therefore lack the panache, polish and skill to place the aircraft squarely on the centre line with all drift removed? Possibly both. A consistently well handled strong crosswind landing is an art on it's own. A thing of great beauty and personal satifaction.
Crosswind landing training in simulators tend to be glossed over,and other sequences given greater priority. Perhaps that explains the reluctance or inability of some pilots to remove drift at touchdown. Considering that inexperienced pilots going from light twins to 737's from CPL graduation, may in their career, have never experienced more than 15 knots crosswind component, (no criticism implied, if only because few light twin trainers have crosswind limits exceeding 15-18 knots) - then one would hope that their simulator instructors would spend more training time on the various types of crosswind landings. A good simulator instructor should not be afraid to demonstrate crosswind landing technique. Something about a picture being worth a thousand words.
Considering the real skill needed to make consistently well judged crosswind landings in a 737 without drift, I doubt if this skill can be picked up by just the occasional crosswind landing in a simulator syllabus. After all, it is known that many airlines limit first officers to strict crosswind limits until command training. Presumably because strong crosswind landings can be a flight safety hazard for low experience pilots. In turn, this suggests more emphasis should be placed on correct crosswind technique during type rating and recurrent training in the simulator.
On the other hand, maybe the instructors point to the FCTM and say "there it is lad - all in black and white - you can safely land without removing drift and without busting the Boeing. In my view this is nothing more than a cop-out and certainly poor training.
A recent amendment to the B737 Classic FCTM, says sideslip only (zero crab) landings are not recommended with crosswind components in excess of 17 knots at Flap 15, 20 knots at Flap 30 and 23 knots at Flap 40. It states this ensures adequate ground clearance and is based on maintaining adequate control margin. This seems awfully vague as if the legal people have had an input into the wording. I am a bit puzzled if this is about engine or flap ground clearance? And also, how does one judge "adequate" control margin?
At first glance, I would have thought that lesser flap settings meant less chance of airframe or engine scrape in strong crosswinds. But the figures in the FCTM given seem to contradict that theory.
Appreciate any constructive opinions as to why would Boeing suddenly publish these crosswind component figures versus flap settings, when since the first 737 flew there was no apparent need?
I have talked to pilots who use the crosswind technique of deliberately not removing drift before touchdown. They argue the FCTM allows that, without damage to the landing gear. That this technique often feels and sounds terrible if touch down is with significant drift, seems not to faze them. Is it because they are tense when faced with crosswinds? Or, because they have not been properly trained and therefore lack the panache, polish and skill to place the aircraft squarely on the centre line with all drift removed? Possibly both. A consistently well handled strong crosswind landing is an art on it's own. A thing of great beauty and personal satifaction.
Crosswind landing training in simulators tend to be glossed over,and other sequences given greater priority. Perhaps that explains the reluctance or inability of some pilots to remove drift at touchdown. Considering that inexperienced pilots going from light twins to 737's from CPL graduation, may in their career, have never experienced more than 15 knots crosswind component, (no criticism implied, if only because few light twin trainers have crosswind limits exceeding 15-18 knots) - then one would hope that their simulator instructors would spend more training time on the various types of crosswind landings. A good simulator instructor should not be afraid to demonstrate crosswind landing technique. Something about a picture being worth a thousand words.
Considering the real skill needed to make consistently well judged crosswind landings in a 737 without drift, I doubt if this skill can be picked up by just the occasional crosswind landing in a simulator syllabus. After all, it is known that many airlines limit first officers to strict crosswind limits until command training. Presumably because strong crosswind landings can be a flight safety hazard for low experience pilots. In turn, this suggests more emphasis should be placed on correct crosswind technique during type rating and recurrent training in the simulator.
On the other hand, maybe the instructors point to the FCTM and say "there it is lad - all in black and white - you can safely land without removing drift and without busting the Boeing. In my view this is nothing more than a cop-out and certainly poor training.
A recent amendment to the B737 Classic FCTM, says sideslip only (zero crab) landings are not recommended with crosswind components in excess of 17 knots at Flap 15, 20 knots at Flap 30 and 23 knots at Flap 40. It states this ensures adequate ground clearance and is based on maintaining adequate control margin. This seems awfully vague as if the legal people have had an input into the wording. I am a bit puzzled if this is about engine or flap ground clearance? And also, how does one judge "adequate" control margin?
At first glance, I would have thought that lesser flap settings meant less chance of airframe or engine scrape in strong crosswinds. But the figures in the FCTM given seem to contradict that theory.
Appreciate any constructive opinions as to why would Boeing suddenly publish these crosswind component figures versus flap settings, when since the first 737 flew there was no apparent need?