reply to post by weedwhacker
...response to a video, Part Deux:
The discussion, as I mentioned, of the two pilots not being able to hit the WTC troubles me, because it is NOT that difficult to do. And, FWIW, it is
ALWAYS easier to fly the real airplane, than the simulator. Also, IF it was not a modern, sophisticated device, but one of the older ones with the
less-than-realistic methods of providing the visual in the 'windshields' then that is a drawback, and possible reason for their 'failure'.
To compare, with a more modern and realistic Level D quality, with a 'daylight' visual system, to possibly include 'wraparound' visuals
(peripheral vision is extremely important and subtly inhibiting if missing), then I think the success rate would improve dramatically, as evidenced in
other videos available on UTube. That show very inexperienced pilots, even laypeople, "hitting" their targets at high speed.
The discussion also devolves into a 'red herring', talking about Dutch Roll...complete distraction, as A) "They" attempted their 'experiment' in
a B-737 Sim, and the B-737 is not really a problem when it comes to tendency to Dutch roll, and B) The B-757/767 models are even LESS likely to Dutch
roll...
In large Transport Category jets, it's the angle of wing sweep-back that determines the tendency to Dutch roll --- and it is the function of the yaw
damper as a full-time monitor to inhibit and 'damp out' any yaw-induced roll that tends to form. For instance, older Boeings (B-707, 727) had
airspeed restrictions when the Yaw Damper was INOP. There are no such restrictions on the B-737, B-757/767. So, in smooth air, like the morning of
11 September, Dutch roll is simply a non-issue.
They talked about aileron flutter, and 'roll reversal' too...related phenomenons, but, again, not pertinent to those Boeings....not unless they were
at very, very extreme speeds, beyond those seen....AND, it has a lot to do with Mach flow, as the air flows over the lifting and control surfaces.
'roll reversing' is, simply, the wingtips flexing as the ailerons are deflected into the high-speed airflow. i.e., if the right aileron moves
'DN', which normally would tend to raise the wing it is attached to, the high forces might flex the wingtip the other way, thus negating the
aileron's effect, or 'reversing' what is intended by the pilot. Boeing wings are much too stiff to flex, like that, at the speeds we assume from
Radar data, and the SSFDR data from AAL 77. More on that -- in the case of B-767s, there are FOUR ailerons total, two each wing. An outboard, near
the tip, and one INBOARD, between trailing edge flap segments. When the TE flaps are completely retracted, ONLY the inboard ailerons function, the
outboards are locked in place. SO. no 'roll reversing' is even possible. Also, as in most modern Transport Category jets, the actual roll control
is accomplished by a
combination of not only the ailerons, but also the flight spoilers. In fact, the spoiler panels begin to rise, on
the wing meant to descend for turn initiation, almost immediately with control wjheel deflection...only needs to turn the wheel more than about 5
degrees or so...might be 7, forget the exact number.
'Flutter', also...function of Mach number (airspeed as a percentage of the Speed of Sound). Any flutter tendency is due to the localized areas of
high-speed flow on the surfaces. BUT, near sea level, even at the airspeeds mentioned, you aren't anywhere near a high Mach number. IOW, the
airplanes typically cruise as fast as M.80, or even M.83 comfortably (although that's not as fuel efficient, but that is beyond the scope of this
discussion). A speed of 460 knots, at seal level, is about M.70 Not an issue there, despite the distracting disinfo presented by
some
pilots.
Finally, at about the 8:00 minute point in the video, discussing the turn before lining up on the Pentagon...really??? The guy (who I already said
sounds like a pilot, to me) thinks that it was a 'professional' turn??? His standards are very low, then -- which, of course, I find hard to
believe, since he promotes himself as an IP and Check Airman. The other vid, showing the NTSB re-creation of that turn and descent, show an what
would be sloppy, in terms of airspeed and bank angle control, IF it was, as he alleges, performed by a 'very professional, experienced' pilot.
Instead, I see a guy who knows how to fly, at the very least the basics anyway, who didn't care a wit about being precise, nor smooth...but he got
the "job" done.
AND, here's where it jumps the shark again...the last bit, the straight-in aiming at the Pentagon??? Easiest part of the whole deal. I do NOT know
who this guy, on the phone, thinks he's trying to fool. He embarasses me, frankly.