Power configuration settings in the pattern

Jaybird180

Jaybird180

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Jaybird180
A few of the airports I operate to/from have non-standard TPA. My instructor wants me to get more into flying by the numbers and has insisted that I roll-out on final "300 and 1". I've had to play with my descent rate. My full attention on landing has been on 3 things:
1- Looking outside
2- Airspeed
3- That's about it

I now need to include the altimeter in my scan, and I believe I can improve things if I also had an idea what the VSI was doing during my patterns. I've NEVER looked at it.

I typically use 1500 RPM in the C-172S abeam the numbers and it has worked in the past, but I need to get better. I'll need to use a lower power setting for the airports that use 1200 and 1500 AGL TPA, but I don't have the data to make an educated guess about my initial power settings.

I'll need to figure out a power setting:
If I want to lose 300ft on downwind at 10deg flaps at 85KIAS
If I want to lose 500ft on downwind at 10deg flaps at 85KIAS
If I want to lose 300ft on base at 20deg flaps at 75KIAS
If I want to lose 500ft on base at 20deg flaps at 75KIAS
If I want to lose 300ft on final at 30deg flaps at 65KIAS
If I want to lose 500ft on final at 30deg flaps at 65KIAS

I thought I'd run the scenarios on my simulator but it's acting ugly. I'm hoping that someone has some data that I can use for power settings. I have an evaluation flight tomorrow. I was going to try a WAG at 1300RPM for 300ft and 1100RPM for 500ft and see what I get.

I appreciate it.
 
Uh, that's not how it's done. Pick whatever setting you like then make adjustments to your glide pattern. If an adjustment causes you to appear to be landing too long (you'll see it right away after the change) widen out, put some flaps out or change your speed to a less efficient one or slip or over-shoot final a bit or "S"-turn or... reduce power if you picked a setting too far out of the ball park. After the change, you'll again see the result right away. Rinse, repeat.
 
300 and 1... interesting take in a 172, given most spam cans don't have a radar altimeter. We use that 300/1 moniker in the -38 because we have one, but even in the T-6 we wouldn't really emphasize that since the only altitude measurement available is the altimeter, and most students are too task saturated to make the conversion when going to an airfield other than home plate. Sounds like a 141 school cosplaying airlines (in fairness, by definition it's what they do).

Doing the teaching thing for as along as I have in wildly diverging environs (both pistons and non-transport turbines), I don't particularly care for an IFResque approach to teaching visual patternwork. I understand it's a manner of behavior that may lend itself to that follow-on automaton crew-cockpit airline thing they're all gunning for, but I don't think it allows for the development of an aimpoint-based crosscheck, which is what VFR flying is fundamental to. I also find operating low-wing loading non-thrust-spool-lag lawnmower as though they're airliners, not a particularly positive-transfer affair when they do get to turbine equipment.

I could tell you how I teach it, but I'm not in the business of giving out flight instruction for free. After all, I'm trying to help the folks on here by exacerbating the pilot shortage via staying in the shadow inventory :D
 
dtuuri said:
Uh, that's not how it's done. Pick whatever setting you like then make adjustments to your glide pattern. If an adjustment causes you to appear to be landing too long (you'll see it right away after the change) widen out, put some flaps out or change your speed to a less efficient one or slip or over-shoot final a bit or "S"-turn or... reduce power if you picked a setting too far out of the ball park. After the change, you'll again see the result right away. Rinse, repeat.
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I’ve heard it as “TLAR” (that looks about right). Too high? Adjust. Too low? Adjust. TLAR? Leave it alone.
 
dtuuri said:
Uh, that's not how it's done. Pick whatever setting you like then make adjustments to your glide pattern. If an adjustment causes you to appear to be landing too long (you'll see it right away after the change) widen out, put some flaps out or change your speed to a less efficient one or slip or over-shoot final a bit or "S"-turn or... reduce power if you picked a setting too far out of the ball park. After the change, you'll again see the result right away. Rinse, repeat.
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I think the standard might be higher than ACS requires, but I don't get to make that call in this instance. In most of my landings I use TLAR as @Matthew mentions and I adjust, but ... it is what it is...I don't even get to use my preferred X-Wind technique, I HAVE to do it the way the evaluator is expecting...again I don't get to make that call for this evaluation.
 
300 AGL at a mile out? No thanks. I’m no expert, but I’m not dragging it in that far. Power off abeam the numbers and if I need more throttle before I’ve got the runway made, then I did something wrong.

But that’s just the way I was taught. My CFIs would gripe if they thought I was “dragging it in”.
 
DaleB said:
300 AGL at a mile out? No thanks. I’m no expert, but I’m not dragging it in that far. Power off abeam the numbers and if I need more throttle before I’ve got the runway made, then I did something wrong.

But that’s just the way I was taught. My CFIs would gripe if they thought I was “dragging it in”.
Click to expand...

In fairness to the OP, you weren't cosplaying 737 in a 172 though, as his/her presumed instructor cadre's apparent insistence he do so.
 
hindsight2020 said:
In fairness to the OP, you weren't cosplaying 737 in a 172 though, as his/her presumed instructor cadre's apparent insistence he do so.
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That is true. Absolutely not being critical of the OP. I do disagree with the OP’s instructor, though.
 
Jaybird180 said:
I HAVE to do it the way the evaluator is expecting...
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Then ask your "evaluator" for his spreadsheet. Be sure to tell him you're looking for one with lots more columns than your OP, one for every five knots of headwind component.

EDIT: Oh, I forgot about base leg. You'll need those 5 kt columns divided into crosswind components in 5 kt increments too.
 
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Jaybird180 said:
I think the standard might be higher than ACS requires, but I don't get to make that call in this instance...
Click to expand...
What does the ACS say about the various types of landings? If you’re confused why the instructor is teaching a specific technique, have a ground session with the instructor and ask them to explain their technique and how it aligns with the AFH, PHAK, and ACS. Literally, line by line. Chances are your instructor won’t be able to do it or will revert to reciting chapter/verse from the program’s syllabus/TCO.

Jaybird180 said:
… I HAVE to do it the way the evaluator is expecting...again I don't get to make that call for this evaluation.
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The only “evaluator” that matters is the DPE. If you’re referring to a stage check, ask the check airman the same questions about techniques v ACS. Somebody is paying these people to teach you something and if you’re cognizant enough to realize they aren’t teaching you something, then you need to take charge and do something about it.
 
Sorry to bother you guys, but this is a "cooperate to graduate" situation. Thought I could get some help here.
 
Jaybird180 said:
I think the standard might be higher than ACS requires, but I don't get to make that call in this instance. In most of my landings I use TLAR as @Matthew mentions and I adjust, but ... it is what it is...I don't even get to use my preferred X-Wind technique, I HAVE to do it the way the evaluator is expecting...again I don't get to make that call for this evaluation.
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300’ / mile is the rule of thumb for a 3 deg glide slope. Do they want you to set up for a 1 mile final at 300’ and then not touch the throttle? Someone else mentioned headwind compensation factors, too. There are a lot of variables that go into this, and there may not be the same answer every time. I get it, you’re expected to perform to what the evaluator wants to see. One of my many CFIs liked to say, “Every landing is a crosswind landing”, every landing is different.
 
What numbers are you using for your standard TPA (1000’?)?

And now you’re trying to adjust for 1200’ and 1500’? Can you just start descending a little earlier and still end up at the 1000’ at the same point you’re used to?
 
Jaybird180 said:
My instructor wants me to get more into flying by the numbers and has insisted that I roll-out on final "300 and 1".
Click to expand...
Jaybird180 said:
I thought I'd run the scenarios on my simulator but it's acting ugly. I'm hoping that someone has some data that I can use for power settings. I have an evaluation flight tomorrow.
Click to expand...
Jaybird180 said:
Sorry to bother you guys, but this is a "cooperate to graduate" situation.
Click to expand...

What is the evaluation flight for? Just curious if additional context for a question which seems to be not providing the answer you are looking for might be helpful?
 
Ask you CFI this question, if I am at 300 AGL as soon as I have turned final as a standard procedure, will I violate the following regulation when I am at a Class D airport?


§ 91.129 Operations in Class D airspace.
(a) General. Unless otherwise authorized or required by the ATC facility having jurisdiction over the Class D airspace area, each person operating an aircraft in Class D airspace must comply with the applicable provisions of this section.
(e) Minimum altitudes when operating to an airport in Class D airspace.
(3) Each pilot operating an airplane approaching to land on a runway served by a visual approach slope indicator must maintain an altitude at or above the glide path until a lower altitude is necessary for a safe landing.
 
I think it shows precision & attention to always be correcting to the pattern altitude for that airport. If there’s a little wind, take that into account also. Let’s say you want to see 1500’ on the altimeter, alway be level or correcting, airspeed too, but don’t get tunnel vision & omit other scan items.

If settled going by abeam, the AOB in the turns will give a little negative VSI, with power reduction. There should be a sight picture once you get more experience, adjust with the VASI if an option. You want your corrections out a ways, smaller adjustments in close.

I flew with a guy a few months ago, he was comfortable being a few 100’ below pattern altitude, with time to correct. He also rolled onto final different every time, usually high.
 
Clip4 said:
Ask you CFI this question, if I am at 300 AGL as soon as I have turned final as a standard procedure, will I violate the following regulation when I am at a Class D airport?


§ 91.129 Operations in Class D airspace.
(a) General. Unless otherwise authorized or required by the ATC facility having jurisdiction over the Class D airspace area, each person operating an aircraft in Class D airspace must comply with the applicable provisions of this section.
(e) Minimum altitudes when operating to an airport in Class D airspace.
(3) Each pilot operating an airplane approaching to land on a runway served by a visual approach slope indicator must maintain an altitude at or above the glide path until a lower altitude is necessary for a safe landing.
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3 degrees is 300 ft/mile, so assuming a 3-degree glide path, no.
 
Jaybird180 said:
Sorry to bother you guys, but this is a "cooperate to graduate" situation. Thought I could get some help here.
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WADR, if the downwind is flown higher than standard you need a wider pattern, i.e., final will be longer. That's why I'm against those guys who say to fly IFR circling approaches at standard pattern altitude and to forget published circling altitudes. If you do that, you've gone a bridge too far in your thinking, imo, and very well could stray beyond protected airspace for obstacles — especially in the dark. (VFR daytime excepted, of course.) Now, your CFI might be similarly possessed and wants you to maneuver consistently to that 300 & 1 spot on the final approach's centerline for the same reason. So, you pick a landmark about one mile from the end of the runway and monitor your closure rate by referencing your altimeter. Unless you've programed VNAV to assist, this is your iPad between your ears' job. I trust you'll do well. You can forget the VSI (I'm the same as you, never looked at it during visual landings in 60 years of flying). You can practice this at Aspen in your sim, where circling approach minimums are obscenely high.
 
I'm not a CFI, just a pilot, but it's the Internet so I'm going to comment anyway. I fly the downwind track at a different distance from the runway track, depending on pattern altitude. So if you're lower, you're closer, and higher it's farther away. Basing it on the angle. The distance is more or less enough that if lose the engine I can still land on the runway. If you do that, I'm not positive, but pretty sure that all the numbers will work the same. Along the way I adjust pitch to maintain the speed I want, I turn based on wind and angles, and I adjust power to control my descent rate.

My first instructors did 2 things that I'm grateful for. One was periodically cut the power in the pattern if I was too wide and then ask "now what are you going to do?" The other was to block off ALL of the gauges if I had my head too focused on the inside of the aircraft.

But getting advice from the Internet rather than you CFI might be a bad plan. Maybe. YMMV. Oh yeah, and I first learned in an aircraft that didn't have one of those vertical descent things. As a consequence, I don't think it's in my scans during landing yet.

edit: re "cooperate to graduate". Fair enough. I'd suggest that you have three separate goals. To get your ticket, to graduate, and to learn how to fly. Those three things are probably coupled together, but not 100% the same.
 
hindsight2020 said:
300 and 1... interesting take in a 172, given most spam cans don't have a radar altimeter. We use that 300/1 moniker in the -38 because we have one, but even in the T-6 we wouldn't really emphasize that since the only altitude measurement available is the altimeter, and most students are too task saturated to make the conversion when going to an airfield other than home plate. Sounds like a 141 school cosplaying airlines (in fairness, by definition it's what they do).
Click to expand...

When did they put one in the T-38? It didn't have one when I flew it and that AT-38B.

But also, that would not necessarily equal 300 feet above runway elevation. :D
 
I like 300 and 1 as a general target. Descent rate speed x 5.

A good traffic pattern is 3 miles from abeam to landing. 1 mile each leg (folks flying 737 patterns in a Cessna 150 excepted). At a constant rate of descent, that's 300' for each of the three legs, with loss of excess during the turns.

But don't make it gospel. Once on base, I've never met a pilot who could not visualize the path to the runway (especially when I cover their airspeed indicator).
 
Jaybird180 said:
…
I now need to include the altimeter in my scan, and I believe I can improve things if I also had an idea what the VSI was doing during my patterns. I've NEVER looked at it.

…

I'll need to figure out a power setting:
If I want to lose 300ft on downwind at 10deg flaps at 85KIAS
If I want to lose 500ft on downwind at 10deg flaps at 85KIAS
If I want to lose 300ft on base at 20deg flaps at 75KIAS
If I want to lose 500ft on base at 20deg flaps at 75KIAS
If I want to lose 300ft on final at 30deg flaps at 65KIAS
If I want to lose 500ft on final at 30deg flaps at 65KIAS
Click to expand...

The VSI should be a confirming instrument, but remember it lags. After a power adjustment, it will take time to settle.

second, there’s no single power setting that’s going to work all the time because of wind/weight/barometer/temp. However, you know 1500 makes you go down about 500ft/min and around 2000 will keep you level at 80 kts, so the answer is in between. More power for drag, more power to go down slowly.

the exercise seems to be about energy management in terms of descent rate vs distance/time. If they want a lower rate, carry more throttle. I’d go around 1850 for 300 fpm down, check for alignment and sink rate visually, then glance at the vsi. More power for more drag, more to go down slowly, less energy for slower speeds. Adjust with small rpm increments.

this thread has a power chart, but not sure it’s useful.
https://www.pilotsofamerica.com/community/threads/c172-pitch-power-setting.107780/

Otherwise, I just want to say good luck, we’re all counting on you.
 
Pinecone said:
When did they put one in the T-38? It didn't have one when I flew it and that AT-38B.

But also, that would not necessarily equal 300 feet above runway elevation. :D
Click to expand...

T-38C conversion included additional avionics. 2001.
 
bflynn said:
The VSI should be a confirming instrument, but remember it lags. After a power adjustment, it will take time to settle.

second, there’s no single power setting that’s going to work all the time because of wind/weight/barometer/temp. However, you know 1500 makes you go down about 500ft/min and around 2000 will keep you level at 80 kts, so the answer is in between. More power for drag, more power to go down slowly.

the exercise seems to be about energy management in terms of descent rate vs distance/time. If they want a lower rate, carry more throttle. I’d go around 1850 for 300 fpm down, check for alignment and sink rate visually, then glance at the vsi. More power for more drag, more to go down slowly, less energy for slower speeds. Adjust with small rpm increments.

this thread has a power chart, but not sure it’s useful.
https://www.pilotsofamerica.com/community/threads/c172-pitch-power-setting.107780/

Otherwise, I just want to say good luck, we’re all counting on you.
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I did spy that thread before posting.
Weather was uncooperative and apparently, I suck worse than the professional weather pontificators. I took leave from work (during 3 projects I'm working on), left home 0600 for a 0930 takeoff time and the conditions were so poor that if I decided to launch I'm sure the evaluator would have got in the right seat, waited for the engine to start and called it a BUST then and there.
 
We got surprised down here too. Sat night, the forecast was beautiful. Sunday morning, it was lifr, fog and rain.
 
TLDR, use whatever power setting it takes for the atmospheric conditions and desired results.
 
Graduate?

I thought you got your private 10+ years ago. Why are you still futzing around with patterns? Roll out 300-1? **** that. That's way too far out. In a single spam can you should be under a half mile when you turn base to final.
 
You're making this way too complicated. You really only need two power settings for appraoch descents. One to give you somewhere around 800fpm for non-precision and another that roughly allows you to track a glideslope at your approach configuration.

Yes, these will need adjustment given headwind components, but that's relatively minor.
 
dtuuri said:
Now, your CFI might be similarly possessed and wants you to maneuver consistently to that 300 & 1 spot on the final approach's centerline for the same reason. So, you pick a landmark about one mile from the end of the runway and monitor your closure rate by referencing your altimeter. Unless you've programed VNAV to assist, this is your iPad between your ears' job. I trust you'll do well. You can forget the VSI (I'm the same as you, never looked at it during visual landings in 60 years of flying).
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As an excercise to get you in position to be at 300 and 1 on final approach, I think most of us could do that as dtuuri has said. Just use that 1 mile out as an aiming point and be at 300 + HAT on altimeter as you constantly adjust throttle and pattern to accomplish that. It certainly is not the usual 172 pattern and the way we usually try to keep us in gliding distance and with our eyes trained on the runway threshold, but it is just an artificial aiming point and altitude that his instructor is asking to demonstrate. Once on that final position however, will just have to keep the power adjusted appropriately for that flat a descent that simulates the ILS. That speed on final however is way off what the 737 is doing unless you are using a crazy fast speed in your 172. That is unsafe, and in my mind, a fail on your test ride unless briefing your examiner that you are cutting power, drastically dropping airspeed, throwing in full full flaps, and possibly slipping on short final. And in fact, without flying the whole pattern at 737 speeds, it almost seems like a pointless excercise anyway.
 
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DaleB said:
300 AGL at a mile out? No thanks. I’m no expert, but I’m not dragging it in that far. Power off abeam the numbers and if I need more throttle before I’ve got the runway made, then I did something wrong.

But that’s just the way I was taught. My CFIs would gripe if they thought I was “dragging it in”.
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Yeah, in a 172, if you can see the runway over the nose, you can make it without theatrics. I sort of became a "chop and drop" aficionado on visual flights. My instructor actually taught this way.
 
4RNB said:
I expect such a chart should include: flaps, power, pitch, descent rate, airspeed.
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I would find that overwhelming.

I like airspeed and glideslope/glidepath as my two more important elements during approach and landing. Power and pitch are what I use to achieve airspeed and glideslope.

Descent rate is a good glance to validate.

Flaps for me starts at first notch when going into landing configuration. Generally flaps then progress to second notch. Third notch of flaps may or may not happen depending on the winds. I do not use 3rd notch for a strong crosswind nor any component of a tailwind.

I had an instructor who wanted me to "fly by the numbers" for approach and landings. All I could think was "paint by the numbers". I have no doubt this works great for some people. For me, it absolutely did not work. I was not assured of the same condition during each landing attempt. Sometimes the winds were greater or less or different direction. Sometimes the tower would have me turn in closer or further out. I may be waiting to see the aircraft in front of me reach final parallel to me before I turn. Fly by the numbers just did not work. For me. That instructor would not budge and that is absolutely their right and their privilege to choose how they want to teach. However as that method of instruction had reached a brick wall for me, it became obvious that it was time for a change. My next flight instructor had a more flexible approach that appeared more tailored to what I was doing. That worked much better for me.
 
4RNB said:
If vfr training, flying stable descent path is good, especially if there is some visual vertical guidance light system
if Ifr, ils or gps gives the guidance.
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Yes. I agree with this.

4RNB said:
Doing such, flying by known settings makes the workload easier.
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I disagree with that. Paint by the numbers. If it works for you then great.
 
4RNB said:
300 and 1 seems meaningless as a standard.
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Except for the overwhelming majority of glideslope/glidepath guidance.
Mongoose Aviator said:
I disagree with that. Paint by the numbers. If it works for you then great.
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You sound like the guys I see who seem to think jet engines have an accelerator pump in the carburetor. ;)
 
MauleSkinner said:
You sound like the guys I see who seem to think jet engines have an accelerator pump in the carburetor.
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I don't understand your response.
I pretty much disagree with anybody who says that a small piston aircraft like a Cessna 172 or Piper 180 should be flown like a jet so you can get used to how a jet operates.
 
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