Jump to content

When do YOU start your descent from downwind?


Bob - S50

Recommended Posts

Just curious.  Pardon me if this has been covered before (didn't see anything recently).  Not saying one is right or wrong.

You are on downwind at pattern altitude.  When do YOU start your descent?  Abeam the numbers?  When you start your base turn?  Some other point?

I'll start.

I start my descent when I start my base turn.

  • Like 1
Link to comment
Share on other sites

Midfield I'm at 22 squared at around 120kts. Abeam the numbers I drop the gear. Confirm gear down, speed below 115, extend flaps to half. This starts slowing the plane down and a shallow descent rate ensues. I take whatever descent this gives me. I pull the throttle back a few inches. I turn base when the runway is about a 45degree angle behind my shoulder. On base I advance prop and mixture and make another throttle reduction. The base to final turn is a major opportunity for glidepath adjustment as needed (often dictated by the wind). If low, start the turn shallow and early. If too high, start the turn later and steeper, even going so far as overshooting the final and doing a >90 turn to realign on it. Angle of attack is maintained at a constant ~1.3vso AOA regardless of how steep the turn is. The speed will vary (don't know, don't care) and the sink rate will vary (steeper = more sink). Usually roll out on final right on glidepath. When I make the final throttle to idle and full flaps calls will be dictated by glidepath and winds. I maintain 1.3 vso most of the way to short final and then have a pretty constant/gradual increase in angle of attack until in ground affect and then I stall/flare it onto the ground.

  • Like 2
Link to comment
Share on other sites

3 minutes ago, midlifeflyer said:

I do it the pretty much same in every airplane I fly.  I start the descent power reduction abeam my touchdown point and base when the approach end of the runway is 45° over my shoulder. 

Sounds like the pretty usual way to fly a pattern but does that mean you *gasp* fly tight turns in the pattern!? Don't you know that tight turns kill!? Not when they're up high of course. They don't choose to cause any trouble up high. But down low on the other hand, they're vicious...

Link to comment
Share on other sites

46 minutes ago, 201er said:

Midfield I'm at 22 squared at around 120kts. Abeam the numbers I drop the gear. Confirm gear down, speed below 115, extend flaps to half. This starts slowing the plane down and a shallow descent rate ensues. I take whatever descent this gives me. I pull the throttle back a few inches. I turn base when the runway is about a 45degree angle behind my shoulder. On base I advance prop and mixture and make another throttle reduction. The base to final turn is a major opportunity for glidepath adjustment as needed (often dictated by the wind). If low, start the turn shallow and early. If too high, start the turn later and steeper, even going so far as overshooting the final and doing a >90 turn to realign on it. Angle of attack is maintained at a constant ~1.3vso AOA regardless of how steep the turn is. The speed will vary (don't know, don't care) and the sink rate will vary (steeper = more sink). Usually roll out on final right on glidepath. When I make the final throttle to idle and full flaps calls will be dictated by glidepath and winds. I maintain 1.3 vso most of the way to short final and then have a pretty constant/gradual increase in angle of attack until in ground affect and then I stall/flare it onto the ground.

I think this is an important point. At least for most of the pilots I've flown with, base leg is the one where they can most easily visualize what the glide path to the runway looks like. It's the best place to make adjustments. It's something I even emphasize in emergency engine out practice.

Link to comment
Share on other sites

Just now, 201er said:

Sounds like the pretty usual way to fly a pattern but does that mean you *gasp* fly tight turns in the pattern!? Don't you know that tight turns kill!? Not when they're up high of course. They don't choose to cause any trouble up high. But down low on the other hand, they're vicious...

I can't always. Sometimes I'm following a 152 in the pattern that thinks it's an A320.

Link to comment
Share on other sites

(Long Body)

Abeam the numbers... (distance from the runway set by wingtip)

gear down and T/O flaps before pattern entry. 90kias, level  on downwind.

turns don't usually exceed 30°.

 

Starting with as many variables removed, minimizes the number of judgement errors available.

 

Best regards,

-a-

 

Edited by carusoam
  • Like 1
Link to comment
Share on other sites

Generally drop gear midfield, start descent abeam numbers, turn base around 45* from runway and  adjust rod based on wind.  Last time out KILG gave me a 360 at about 600 feet , a good question is how many bring the gear up or leave it down when given a 360 on final by ATC.  A buddy of mine had a gear up by not remembering when back on final..oops

Link to comment
Share on other sites

I start my descent abeam the numbers..  

Long Body:  Speed Brakes and gear on the 45, App flap before turning downwind @100 knots, full flap before turning base @ 90 Knots (cleared to land and no heavy winds) , turn base at runway under the wing tip and  TD zone 45 deg behind), approach at 75 knots, decide if speed brake is needed... Land..

  • Like 1
Link to comment
Share on other sites

I have flaps to Takeoff no later than midfield, preferably at pattern entry with runway just inside wingtip. Same for speed at 90 mph, prop full forward. Abeam intended point of landing (just before reaching the numbers), drop gear and begin descent. Turn base when runway is ~45° behind my shoulder. On final, pitch for speed, power for altitude, roll wings level at 85 mph slowing to 75 mph on short final (or 75 mph minus 5 mph for every 300 lbs I am below gross for that landing).

Throttle goes to idle when I have the runway made without it. Roundout just above the runway, hold her off and touchdown just after the stall horn sounds.

No banks beyond 30°, with a bank target around Standard Rate. If I overshoot final, just hold the bank and fly back towards the runway. If I'm still out of alignment by short final, push the throttle in, raise the gear and go try again, paying better attention and getting it right the second time. Retard throttle early, to not blow through 1000' agl; flaps and gear as on the first try, watching speed, distance and glide path closer than before.

Edited by Hank
Link to comment
Share on other sites

Long body established downwind at 17" leave the prop at cruise and pull the power to 15" at midfield, Approach flaps before turn to base, trim up to chevron on AoA. airspeed still at 90 kts. Base to final turn and trim up to bulls eye (Vso 1.3) on AoA, reduce the power to 12" airspeed drops to 80 kts. established straight and stable on final decide on full flaps and added them about 3/4 mile from the runway, trim to relieve yoke pressure, Final gear check over the fence, pull power and hold attitude till on the ground.

Link to comment
Share on other sites

19 hours ago, midlifeflyer said:

I do it the pretty much same in every airplane I've flown since I was a student pilot.  I start the descent power reduction abeam my touchdown point and base when the approach end of the runway is 45° over my shoulder. 

+1. Me too.  The gear has been down for a  couple of miles by that point.  Distraction is what causes gear ups and the likelihood of distraction goes up quite a bit in the pattern, so my gear is down before I get there.

Power back and half flaps abeam the numbers at 90 KIAS, sometimes the rest of the flaps on base and 85 KIAS.  I use the rest of the flaps if I need to slow down for some reason, but normally will land at half flaps or no flaps, almost never full flaps.  75 over the fence.  Square pattern so I can look right on base for anyone coming in behind me.  My home base has two parallels so I am always thinking about that guy on the other parallel who flew a tight pattern, blew through his final, and is now on mine.

Edited by jlunseth
Link to comment
Share on other sites

Interesting.  So far there are only two of us that don't descend until we turn base.  Since others have provided longer more detailed answers, here is more on what I do.

Approach the airport at 20" and 2200 RPM, about 125 - 135 KIAS

Approaching the 45, reduce to 15" which slows me to about 105 KIAS.

Abeam the numbers, gear down but maintain pattern altitude and let the speed bleed off.  Once gear is down and green, select full flaps while trimming nose up at the same time.  Still at pattern altitude.  Once flaps are down, look over the shoulder to see how it looks.  Usually good by the time flaps are down.  Start the turn and the descent and pull the power, often all the way to idle while I slow to 80 KIAS.  While the power is at idle, push the prop all the way back in.  Use the pitch to control altitude for a normal looking base that will roll me out on a normal glideslope, use power to maintain 80 KIAS.  On final wings level, power back to slow to my computed approach speed and pitch to maintain the visual glideslope.  Add power when needed to maintain speed on final.  Over the overrun (or simulated overrun), smoothly reduce power to idle and perform a slow gradual flare.

If I'm solo, grease it on.  If there is someone with me, plop it on.  How do it know?

Link to comment
Share on other sites

2 hours ago, Bob - S50 said:

Interesting.  So far there are only two of us that don't descend until we turn base.  Since others have provided longer more detailed answers, here is more on what I do.

Approach the airport at 20" and 2200 RPM, about 125 - 135 KIAS

Approaching the 45, reduce to 15" which slows me to about 105 KIAS.

Abeam the numbers, gear down but maintain pattern altitude and let the speed bleed off.  Once gear is down and green, select full flaps while trimming nose up at the same time.  Still at pattern altitude.

There may be less difference than you think between abeam and turn base as techniques, depending on what "start descent" means. 

For me, "start descent" means to put the airplane into the configuration I want for the descent. It doesn't necessarily mean reduce altitude at that point. With that in mind most of the difference between our techniques is a small one. Let's compare my "45-entry standard" pattern to yours at similar points  and perhaps you will see what I mean. My J speeds are about the same as yours but since this SOP is universal for me (multiple makes/models and no matter where I enter the pattern)  and airplanes are different, I'll leave the speeds and power settings off.

Descending to the airport. I have been reducing power incrementally to a target number. 

Leveling off at pattern altitude, my gear comes down when at pattern altitude within 3 miles of the airport (kind of like @jlunseth). There's no power change; the power setting I targeted during the descent gives me my target traffic pattern airspeed with the gear down (I'm lazy that way :D).

Abeam my touchdown point, I reduce power to a target setting to get to a target airspeed for the descent from the pattern and deploy flaps. Like you, I maintain level flight until I reach my target descent airspeed.  As I reach that target airspeed, I trim to capture it and  allow the airplane to descend. 

I think the only real difference between us is timing the airplane's loss of altitude from pattern altitude. Mine is tied more to my configuration than my location, although I will not begin the base turn until that initial descent airspeed is captured and stabilized (that laziness again ;)) 

Link to comment
Share on other sites

No, middie, I actually start descending [losing altitude] abeam my intended point of landing [just before reaching the numbers]. That's when I drop the gear and retard the throttle somewhat, establishing ~300 fpm descent. My altitude target is 1000 agl downwind, Takeoff flaps, full prop; turn base ~800 agl; turn final ~500 agl. If the approach is clear, throttle is often to idle almost 1/4 nm before the numbers.

It's all technique, they all work. But the way these are written, some of them make me uncomfortable . . . probably be different riding along in the plane. chirp chirp

  • Like 2
Link to comment
Share on other sites

4 hours ago, Hank said:

No, middie, I actually start descending [losing altitude] abeam my intended point of landing [just before reaching the numbers]. That's when I drop the gear and retard the throttle somewhat, establishing ~300 fpm descent. My altitude target is 1000 agl downwind, Takeoff flaps, full prop; turn base ~800 agl; turn final ~500 agl. If the approach is clear, throttle is often to idle almost 1/4 nm before the numbers.

It's all technique, they all work. But the way these are written, some of them make me uncomfortable . . . probably be different riding along in the plane. chirp chirp

Yep. For the most part they are all pretty minor variations on a theme.

Link to comment
Share on other sites

7 hours ago, midlifeflyer said:

There may be less difference than you think between abeam and turn base as techniques, depending on what "start descent" means. 

For me, "start descent" means to put the airplane into the configuration I want for the descent.

 

By start descent, I mean loss of altitude.

  • Like 1
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.