Pattern procedures

[ralphyoung]

I got my tail wheel training recently in a 65 HP Cub and I have been doing some pattern work in an 85HP stroked Cub. But I need some pattern procedures in my 48 stock 170 to work on and then modify to suit me and my aircraft. I tried 2000 RPM on 500' AGL downwind at end of runway with one notch of flaps but it is still hard to get it slowed down to carry 70 MPH to short final. Then I tried 1500 RPM with carb heat and one notch of flaps, second notch on base and third notch on final when I know I have the field. I would like to hear how others fly their "standard" pattern. I think I am at the stage where I need to get a good solid pattern procedure before I start fine tuning it with experience. Al thoughts appreciated.

[KS170A]

Then I tried 1500 RPM with carb heat and one notch of flaps, second notch on base and third notch on final when I know I have the field.

This is the closest to what I use. When I transitioned to jets, I asked a similar question. The veteran told me "whatever gets the job done." Since then, that's what I've used in all airplanes I fly whether my 170, a turboprop or turbofan. That said, yes, there needs to be a point of reference, and the 1500 w/ heat & 1 notch of flaps is about as good of a starting point as any. Key elements are a stabilized approach and speed control. Technique and/or numbers will also vary slightly depending on if the runway is a short grass strip at high elevation or long paved runway close to the ocean, just you solo or loaded to max weight. Hence, "whatever gets the job done!"

[ralphyoung]

Josh, I read that loud and clear! I am looking for a "Baseline" to develop an an understanding of the aircraft. I am fairly confident of my Cub skills and would like to get as comfortable in the 170.

[counsellj]

500' AGL downwind and only offset about 600'. 2000 RPM = 60-70 mph. Abeam touchdown point, 1200 RPM, 30 flaps and I use a continuous turn to final at 60MPH. Final I use nothing faster than 60 for most of my flying. 50 if I'm light. Power on final is almost always idle, and slip as necessary if still high.

If you are looking for a 70mph final, I would try holding about 1500 RPM on the base/final leg and the same 30 flaps. Trim Trim Trim!

Jughead

[bagarre]

Keep in mind, tachometers can be off by 200 or more RPM and airspeeds can be off by who knows how much.
I'd be looking out the window and work the levers to make the picture look how you want it.

For my plane, 1500ish abeam the numbers and 20 degrees flaps to slow it down to around 80. Down wind is 70ish, adjusting power for height. I put 30 down on final and adjust the throttle so I hit near the numbers around 55, but who's looking at the air speed at that point??.
If I'm too high and idle power wont bring me down, I'll pull the last 40 degrees.

[48RagwingPilot]

In my '48 at neighborhood airports I fly pattern altitude (1000' AGL) offset by about .6 mile (I.e., the runway is even with middle of my strut). Abeam the numbers, I pull power to between 1200-1500 rpm, apply carb heat and pitch for 90 mph so I can pull 30 degrees (all) of flaps. I don't see a need to mess with lesser flap settings. I then pitch with the trim wheel for 70mph and adjust the throttle for a 500fpm descent. I slow a little more on base and when I turn final pitch for 60-65 mph and adjust the glideslope with throttle and slipping as needed. Consistency in the approach works best for me so I can concentrate on the landing phase. Over my aim point, I pull power and execute the landing method chosen earlier, with a mindset ready to improvise. I'm not sure of my touchdown speed, but can land in 500-700 without trying and shorter if I work at it. In the backcountry, where I fly regularly, all bets are off; but, the aforementioned pattern protocol (as varied to simulate backcountry strips), makes adjusting on the fly that much easier.

[bagarre]

On the other hand, this past Sunday I had a 50 degree crosswind that was 24 knots gusting to 33. I didn't use any flaps, and I kept it flying at 75-80 all the way to the ground with heavy gusts making it even harder to deal with the large crosswind component. Having a 150 'x 5000' runway helps, but taxiing was even harder than landing.

I tend to use more flap when the crosswind is blowing to help slow up the plane quicker once on the ground (along with a lot of brakes).
Full flap and a little steeper approach, put it on the mains and hit the brakes. You're down and stopped before the wind can push you around.
Home field is 2400x40
But, I'm one of those dangerous types that wheel land all the time.

[KS170A]

I tend to use more flap when the crosswind is blowing to help slow up the plane quicker once on the ground (along with a lot of brakes).
Full flap and a little steeper approach, put it on the mains and hit the brakes. You're down and stopped before the wind can push you around.
Home field is 2400x40
But, I'm one of those dangerous types that wheel land all the time.

I would subscribe to this method, also considering you could use the flap retraction as a sort of "lift dump" to put more weight on the wheels quicker.

[LBPilot82]

Video example in this post:
http://www.cessna170.org/forums/viewtop ... 319#p92712

Does everyone else dump the flaps right at touchdown? It seems to be something that takes practice to make perfect as Arash has clearly demonstrated but too often when I have tried to play with flap settings while still moving, things have gotten very interesting very quickly (not knocking your technique Arash, just watching and being impressed ). Obviously the benefits of getting the weight on the wheels helps maximize braking but I wonder what the consensus is???

Patterns where I come from are always at 1000 agl. I usually use around 1800-2000 rpm depending on weight to get 80-85mph... no flaps, no c/h. Abeam the numbers, c/h and power to 1200-1300 with first notch of flaps, speed 80. Base turn, second notch of flaps, speed 70. Final, third notch flaps speed 65 slowing. Short final, fourth notch, speed 60. Maybe my technique is off, or maybe I'm just scared of the brakes, but I don't know how some of you can make those 300-500 ft landings consistently. I always enjoy seeing/hearing other peoples way of doing things in order to keep improving.

[GAHorn]

I'm always open to new methods Richard. I had one instructor chastise me big time when I retracted the flaps after touchdown. He said its a bad habit and in more complex aircraft there are no configuration changes until you've pulled off the runway. I'm a rookie and by no means have any of this figured out, so I try to learn all I can from everyone I meet!

Ask your instructor if he uses ANY DIFFERENT techniques tailored to the specific airplanes he flies...or does he mechanically/unthinkingly stick to only ONE method for ALL airplanes regardless of aircraft differences.

The REASON differences are taught is because different aircraft models require different techniques.

Personally, I retract flaps immediately after landing/during roll-out in order to make braking more effective (more weight on wheels) and to reduce the effect of wind on the rollout (because it increases rudder effectiveness.)
However, I'm doubtful my technique in my B-model will exactly apply to your 48 ragwing, but might be helpful.
On downwind...BEFORE reduction of power, while exhaust-heating is more effective, I FIRST apply carb heat.
THEN I reduce power to about 1700 RPM. As the airplane slows it gets nose-heavy....THEN I add one notch of flaps, and VOILA!...the nose is not heavy anymore and no trim change was required.
Slowing still further, as the nose gets heavy I add addt'l flaps to bring the aircraft back into trim. Eventually, with landing flaps applied (usually 30-degrees in the B-model but when heavier, full/40-degrees are used) the airspeed settles around 65 mph IAS and I trim as necessary to arrive over the threshold at 60 mph (plus or minus depending upon wind conditions....gusty? then more speed.) While on final if not before, (this is a personal judgement call) I remove carb heat. (This sets up for a full-power go-around. Also, since the carb has been well heated by now, carb heat is unlikely to be necessary and I don't like the cointinously/rich-mixture condition carb-heat creates, and it re-establishes filtered air for ground ops.) Touchdown on the wheels if strong crosswind and quickly retract flaps and get tailwheel on ground and aggressive braking to slow quickly....or Touchdown in 3-point if short/rough/soft field.
Hope that helps.

[GAHorn]

It's a lot easier to just switch to a different instructor George. Some of them are too set in their ways for me to come along and start questioning their methods. Luckily there are lots of good instructors to choose from.

I see your point! (Of course, the BEST instructors are capable of learning from their CLIENTS as well.....It's a two-way street! I suspect you could teach HIM a few things!)

[LBPilot82]

I see your point! (Of course, the BEST instructors are capable of learning from their CLIENTS as well.....It's a two-way street! I suspect you could teach HIM a few things!)

Boy isn't that the truth!! I have always tried to learn from my students who are more familiar with something than I may be, particularly their OWN airplane. Any instructor who tells you your technique is wrong simply because that isn't the way he/she does it should be promptly dismissed. While there is nothing wrong with questioning technique or suggesting something new, instructors should always keep an open mind to learning just as the student must.

I might have to start playing with retracting flaps after landing and seeing if I can get comfortable with keeping directional control. I think that with few exceptions, this is the most effective technique for getting down and stopped quickly in any GA aircraft.

[GAHorn]

Richard, I was just in your neck-of-the-woods (KLAS/Embassy Suites for 4 days) and am kicking myself for not contacting you.

N E X T - time!

[Poncho73]

I got my tail wheel training recently in a 65 HP Cub and I have been doing some pattern work in an 85HP stroked Cub. But I need some pattern procedures in my 48 stock 170 to work on and then modify to suit me and my aircraft. I tried 2000 RPM on 500' AGL downwind at end of runway with one notch of flaps but it is still hard to get it slowed down to carry 70 MPH to short final. Then I tried 1500 RPM with carb heat and one notch of flaps, second notch on base and third notch on final when I know I have the field. I would like to hear how others fly their "standard" pattern. I think I am at the stage where I need to get a good solid pattern procedure before I start fine tuning it with experience. Al thoughts appreciated.

I checked myself out in my 48 so I have never had another opinion on it…., but this is what works for me with my 48….

- Example circuit - Brampton Airport, Ontario, Canada - 800AGL circuit height, left hand circuit...using standard power settings and a "cruise Power" downwind.
– mid-downwind I apply carb heat "hot"….another check I recommend adding to your checklist at this time is - tap the toes brakes, making sure they are available when needed – good airmanship stuff…. Just before turning base, I reduce power again, but I can't say by how much I just do it by feel...maybe 1800 or 2000 rpm enough to slow the aircraft for a targeted 90mph immediately after base roll out. Once established on base, at flap speed (90 max) or slightly below, I apply full flap, slowly but continuously until reaching 30 degrees. (Note: the Owner’s manual for the 48 is not specific – Section 1, Operation and Performance, states: use whatever flap setting is desired. Section II, states the landing flap is 30 – fully down). So it’s your call, but I have found by getting to the full flap position on base it puts me on a very stable final which I aim for final at 500 AGL, fully trimmed and on speed with nothing to do but fly to the runway. Speed for final is your call, the Manual states 70 – 75 mph for approach, which is fine in a busy circuit, but flying 60 – 65 mph is good too, again whatever is desired for the condition….use power to maintain sink rate 500fpm and pitch to control speed. I leave the carb heat “hot” until on ground. IMO this allows the aircraft to slow better after throttle cut performance, as the engine is down to the appropriate idle RPM. I have retracted the flaps after touchdown - but only at a speed that is not distracting from the job at hand – which is, maintaining direction control! However, it’s my option, the flaps on 48 have very little “lift dump” effect…I would think this is more of a “B” model factor. My professional belief on post-touchdown configuration changes is – not to do them. The least amount of hand movements post-touchdown is the safest practice. I’ve investigated plenty of accidents were pilots have moved levers, switches and handles after touchdown resulting in runway excursions and in some cases accidental gear retractions….obviously gear ups are not an issue for us, but all I’m just saying is it’s good airmanship not to overwork a simple task….maintain control....this IMO is a good practice no matter what your flying. Once clear of the runway, flaps up, carb heat cold, trim reset. It's pretty simple really. Try to build your procedures around the flight manual speeds, they are actually pretty good considering when the flight test data was developed.

[bagarre]

The least amount of hand movements post-touchdown is the safest practice. I’ve investigated plenty of accidents were pilots have moved levers, switches and handles after touchdown resulting in runway excursions and in some cases accidental gear retractions….obviously gear ups are not an issue for us, but all I’m just saying is it’s good airmanship not to overwork a simple task….maintain control....this IMO is a good practice no matter what your flying. Once clear of the runway, flaps up, carb heat cold, trim reset. It's pretty simple really. Try to build your procedures around the flight manual speeds, they are actually pretty good considering when the flight test data was developed.

Agreed.
I've tried dumping flaps on touch down and it just seems to over complicate an already complicated ordeal.
Not sure how much 'lift' you're dumping sine 40 degrees of flaps is already creating more drag than lift.
You do get some rudder authority back which is good. Specially since the act of moving the johnson bar while rolling out can put you in a situation that you NEED more rudder authority.
Besides, a little forward stick on a wheel landing will dump more 'lift' than dumping the flaps. In fact, it will press your tires onto the pavement more which improves braking. In a 3 pointer, you dont need to dump lift 'cuz you're supposed to be stalled when you touch down.

And, if it was a better way to land, Cessna would have detailed it as such in one of their approved publications