ARC = Abnormal Rwy Contact (includes Rwy contact by tail, cowl, I/B Flap, hard Ldg, &ct)
A comment in message #45, dated July 23rd:
"... Perhaps it wasn't so much a case of too much wing down, as it was a case of not being properly aligned with the runway ... trying to align with the centreline ... too late ... should have been going around ..."
ARC-Investigators, and even the ALAR Task Force, haven't yet sorted these "alignment" variables, nor gathered and labeled the various cases. Maybe pilots could provide investigators & FDM some guidance on taxonomy for those alignment variables. [Some of these ARC-investigations (employing professional investigators) have been disgraceful.]
Maybe the ALIGN task conflates two, or three, differing pilot tasks?
AutoLand guys might consider the "ALIGN" function as the late de-crab YAWing motion (to match HDG with Rwy so that yaw-angle at touchdown is zeroed).
Pilots also sometimes must manually "align" or correct to COURSE (or to centerline) after a non-precision approach, or after an autopilot deviation near DH. This is the lateral L-R motion, toward centerline (but not overshooting). For FDR/FOQA/FDM, data-guys would consider this "alignment" as zeroing FDR's Loc-Dev.
?? For long-body airliner, in stiff x-wind landing with a planned Crab Angle, the "align" task might include visual line-up near the up-wind rwy edge -- so as to insure MLG does touchdown on concrete (??).
This ALIGN task (sometimes withOUT x-wind), while too-low, was a factor in other ARC-mishaps. NTSB recently released this case, where the pilot attempted a more perfect ALIGNMENT nearing DH -- then his correction overshot Centerline, touchdown with LHS MLG in the grass: thus achieving both an ARC (RHS I/B Flap and RHS wing tip), and also logging a USOS (LHS MLG off rwy at touchdown):
DCA10IA015
There are three FDR plots available for the above mishap, AA-MD8 ARC, at 300' the Autopilot's tracking was a mere .28-dot Right, disconnected A/P, corrects, touched-down Loc-Dev shows .28-dot Left (photo evidence records that touchdown about on the Rwy's left Edge Line at 8000+ remaining, or 75' left of centerline), with the LHS MLG in the sod, just after the RHS Wingtip & RHS I/B Flap had contacted Rwy. [Interesting that Loc-Dev never exceeded the airline's one-third Dot triggering the "Go Around" call-out from a perfect FO-PM.]
Another example of L-R course correction inducing an ARC-wingtip was
ANC06IA054"... I pointed out runway 19R. While maneuvering to line up on the runway, we overshot...."
One investigator related that he considered this mishap as more of a Go-Around ARC (Turbojet's spool-up delay?), since the pilots had initiated G/A prior to the wingtip-ARC.
More recently, during strong x-wind at NYC's KLGA, there was an ARC-Wingtip, after a displaced-final approach course, correction to centerline, x-wind; this also maybe more of a G/A phase wingtip-ARC (turbojet's spool-up time-delay?):
AA366 / 5May11 LGA MD83
N966TW Lndg-GoAround ARC- wing-tip
http://www.faa.gov/data_research/acc...a/D_0506_N.txt
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Another common ARC-result has been that the mishap-pilots were
completely unaware that their landing had included any Abnormal Rwy Contact, or off-rwy touchdown. Thus, occasionally, the ARC-mishap wasn't recognized by the humans, nor recorded in the aircraft logbook. Extreme examples of this ALA- lack of recognition (really more of a task-fixation) are available, eg, on
26Aug64 a B707-331 N787TW landing mishap at Kansas City MKC , where both MLG impacted the dike just prior to the Rwy Threshold -- pilots were not aware that the MLG had separated from the aircraft prior to their landing on the Rwy36, pilots were slow to realize that the airliner couldn't roll during attempted taxi.
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A380 limit geometry (pitch & roll) , for ARC- #4 Engine, was cited in message #44:
"... 3 p / 7.1 r -- Outer Engine Scrape ... Ref A380 FCTM ..."
Hmmm, A380's geometry-limited bank angle cited was 7.1 degrees of roll.
ALAR Briefing Note
8.7 — Crosswind Landings [PDF 163K]
Figure 3 = plots of "Crab Angle / Bank Angle Requirement in 30-Knot Crosswind"
Read it yourself, 30Kt x-wind needs ~ 9degrees bank for a Zero Crab Angle at touchdown. Chart notes suggest mixing crab & bank for combination of 5degrees Bank with 5degrees Crab. [Therefore, the pilot would have a 2-degree margin of safety, is that enough?]