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Old 30th Jan 2005, 22:30
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NickLappos
 
Join Date: Apr 2003
Location: USA
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We always learn things!

Goeff and Ogsplash - Helicopters are ALWAYS Cat A on the approach plate, guys, no matter what speed you fly. That is because you don't have a 1.3 Vso (unless I forgot and left the wings on my helo). The limits to maneuver are meaningless to a direct lift aircraft that is at its best maneuver condition when a starch-wing is teetering at the edge of control. I agree with you Ogsplash, the slow down usually starts much earlier, since you usually break out at 500 or 700 feet, where you are miles away from the turnoff.

Crab - 5 knots of speed at 130 is worth the entire ILS ROD, so a few knots is powerful, and easy. If you juggle the collective, be my guest. I use the first 4 knots for altitude, then back off a little collective.

Lightening_Boy - a few seconds difference makes no real problem, really. If your glideslope fails, you are non=precision, anyway.

Gear speed is a real concern, I agree. If you can't drop your wheels at 130, you are perhaps flying the wrong type, since an S-76 is 130 gear down speed. I do agree that I want the wheels down at the FAF, and if your gear speed is much less, be at the gear speed. It is tough enough at the bottom without hearing that terrible scraping sound!

It is fairly easy to stop a 130 knot helo when at 1/4 mile from the threshold, and you have a further 4000 feet to the tower/terminal, (giving you the much better part of a mile, if you are only visual just as you hit minumums). This uses about 7 degrees nose up attitude for most helos, an easy thing visually. If you can't do this, can I suggest perhaps dentistry? ;-)

Seriously, I use 125 for most ILS and find it very easy, but if you are right at mins, and it is a small airport, and its night, I get down to perhaps 90. I flew several hundred approaches to zero zero during a test program once, and found the precision of localizer glideslope retention much better at the higher speed. The turn rate is based on v squared, so if you are at 70 you have almost 4 times the turn rate for 1 degree of bank as you do at 125. This means your flying has to be more precise to achieve the same nav accuracy, or stated another way, your precious workload is being used to keep sharp bank when it could be helping you maintain other awareness.
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