While I agree with Vic and Bob and fly my approaches at the higher airspeeds for comfort and ATC spacing, just be aware that if you're going to use Cat A minimums, they require 90 kts or less approach speed. I also agree that flaps should be lowered only when the field is in sight. I just flew my BFR/IPC ride on Friday and I had this discussion with the check airman who agreed wholeheartedly: about 100 kts on final, no flaps until the field is in sight at minimums. Plenty of time to slow down to flap speed. Field not in sight, just add power and go missed, flaps are already up.
Personally, I htink 80 knots in actual IMC in the 10 is a little low. Just my opinion.
I like very small changes when in actual IMC.
Vic
Vic, I pretty much agree with you, with one exception: When the visibility is down to 1/2 mile at night. This means that at DA you see, a bit hazy, the approach lights and nothing else. No runway lights, no VASI. As far as I'm concerned this is IMC, right down to the ground. And, like you, I want only small changes in these conditions. So that means flaring at 100 kias and flaps in trail (okay for a very long runway), or pre-configuring much earlier. For these conditions I use half flaps and 80 (+5/-0) kias. Yes, that means more work on a miss. But the -10 climbs okay with half flaps, and the flaps retract slowly enough that you can react to the pitch changes.
I can't argue with you. However, I don't fly when it is 1/2 mi at night. At least I wouldn't plan on it.
Vic
Bevan,
Without having tried this, it looks to me like fine control to stay on GS will be hard. The only control you can vary is power. Also with a headwind you may end up with a fairly high airspeed, to keep your ground speed at the chosen number. Or with a good tailwind, end up close to stall speed. I wonder if you wouldn't be better off turning off the vertical autopilot mode. Then you can manually stay on GS with pitch trim and/or power changes.
I can Vary the rate of descent directly on the face of the AP and with power of course.
Bevan.
I also use 90-100 knots neutral flaps until the runway is in sight and then flaps as needed
if using the trutrak vision AP I prefer to ask for LPV approaches instead of ILS as the AP flys that great
Alan
N668G
Actually with the AP engaged in vertical descent mode power will not change the rate of descent. The AP will change the pitch as needed to keep it at the set rate. Adding power with the autopilot keeping the vertical rate fixed will result in increased airspeed, shallowing the descent angle so if low on the glide slope, adding power will result in you re-intercepting it. But it may be tricky to fine-tune. Yes, you can certainly change the AP (500, 400, 600 ft/min) to stair step down the GS.
Just watch out if you have a 30 knot tailwind. Then a 94 knot ground speed means 64 kias - pretty close to stall.
To keep things really simple, I use 120 knots for everything in the approach environment.
16 inches produces 120 knots in level flight for maneuvering and holds.
10.5 inches produces 120 knots and a 600 fpm descent which closely matches the glide slope (no wind).
Full power produces 120 knots and a good rate of climb for the missed.
This way I only have to trim once, for 120 knots.
120 knots makes for easy math--two miles per minute (no wind).
Flaps up throughout obviously, unless I break out and am going to land.
Recently flew an ILS to minimums at SPI and had plenty of time to slow and lower flaps for landing once I broke out.
I have an O-360 with CS prop. RPM stays at 2400 all the time unless climbing on the missed.
LeRoy Johnston RV-6A Esperanza 1100 hours.
I'm in the Vic camp as far as speed goes. I fly very close to the RV6 above.I tried 115kts/0 flaps yesterday and it worked well.
For Dave, the 0 flap position is recommended for takeoff and climb. Raise to reflex position when at cruise altitude. Using 0 for the approach sets you up for the missed.
Also, if your climb and approach speeds are the same, then you don't have to mess with either flaps or trim on the missed - as pointed out earlier. I may try 120 kts as a compromise. My usual climb speed is 130 kts, in order to keep cylinder head temps below 400. 120 kts will work initially.
Personally, I htink 80 knots in actual IMC in the 10 is a little low. Just my opinion.
I fly all holding procedures at 18" of MAP which gives about 120 KIAS. The autopilot is comfortable there, and I think ATC appreciates the speed. Usually when it's IMC there are other airplanes around and sequencing is easier at these speeds.
Crossing the FAF I will bring the flaps out of reflex, and slow to 105-110. I do NOT add any more flaps unless I break out visually and am assured the runway is in sight and I can execute a normal landing. Even with a breakout at minimums, with 110 KIAS and flaps out of reflex, the 10 will have no problem slowing to final flap speed and making a normal landing, without using excessive amounts of runway.
On the other hand. If you have the flaps hanging out and execute a go around in IMC without being prepared for the pitchup that the 10 will give you, you are going to have your hands full at the most inopportune time.
I like very small changes when in actual IMC.
Vic
Personally, I htink 80 knots in actual IMC in the 10 is a little low. Just my opinion.
I fly all holding procedures at 18" of MAP which gives about 120 KIAS. The autopilot is comfortable there, and I think ATC appreciates the speed. Usually when it's IMC there are other airplanes around and sequencing is easier at these speeds.
Crossing the FAF I will bring the flaps out of reflex, and slow to 105-110. I do NOT add any more flaps unless I break out visually and am assured the runway is in sight and I can execute a normal landing. Even with a breakout at minimums, with 110 KIAS and flaps out of reflex, the 10 will have no problem slowing to final flap speed and making a normal landing, without using excessive amounts of runway.
On the other hand. If you have the flaps hanging out and execute a go around in IMC without being prepared for the pitchup that the 10 will give you, you are going to have your hands full at the most inopportune time.
I like very small changes when in actual IMC.
Vic