Circuit shape
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[QUOTE][I am thinking of a Rate 1 turn./QUOTE]
Turns in the circuit are not necessarily Rate One which is 30 seconds for a 90 degree turn and is normally only applicable to instrument flying. The first climbing turn on to the first crosswind leg should be made at 30 degrees angle of bank whereas a Rate One turn with a typical 80 knot climb speed gives you around 15 degrees angle of bank. The longer you have one wing lowered in a high wing aircraft the more exposure you have to not seeing another aircraft in that blind spot.
Turning to downwind leg and depending on wind direction and speed, you may consider conducting a climbing turn to the downwind leg in order to attain the correct spacing from the runway. Do that at 30 degrees angle of bank for same reason as earlier. Turning base again for for 30-40 degrees angle of bank which is considered a medium turn. Same for turning final.
Turns in the circuit are not necessarily Rate One which is 30 seconds for a 90 degree turn and is normally only applicable to instrument flying. The first climbing turn on to the first crosswind leg should be made at 30 degrees angle of bank whereas a Rate One turn with a typical 80 knot climb speed gives you around 15 degrees angle of bank. The longer you have one wing lowered in a high wing aircraft the more exposure you have to not seeing another aircraft in that blind spot.
Turning to downwind leg and depending on wind direction and speed, you may consider conducting a climbing turn to the downwind leg in order to attain the correct spacing from the runway. Do that at 30 degrees angle of bank for same reason as earlier. Turning base again for for 30-40 degrees angle of bank which is considered a medium turn. Same for turning final.
The first climbing turn on to the first crosswind leg should be made at 30 degrees angle of bank
Ted
Agreed, Ted D Bear!
30 deg AOB in a climbing turn?
When you want to go up you need as much of your lift going as vertical as possible, not horizontally.
Basic stuff, really. (I mean it... usually covered before stalls....
)
Speaking of which....
To any students who want to do a 40 deg turn into base as normal procedure, I hope your life insurance is paid up. That's bordering on a steep turn, not medium.
Let's see if you remember what happens to stalling speed with increased AoB (read as load factor) and relate this to an wing drop/incipient spin when close to the ground.
Definitely not a standard manoeuvre now, is it?
S-turns might be taught as a way to lose a lot of height rapidly to correct an overshooting FLWOP, but the student must ALWAYS be made aware of the risks involved due to reducing IAS (due increased drag) and increased load factor.
30 deg AOB in a climbing turn?
When you want to go up you need as much of your lift going as vertical as possible, not horizontally.
Basic stuff, really. (I mean it... usually covered before stalls....
)Speaking of which....
To any students who want to do a 40 deg turn into base as normal procedure, I hope your life insurance is paid up. That's bordering on a steep turn, not medium.
Let's see if you remember what happens to stalling speed with increased AoB (read as load factor) and relate this to an wing drop/incipient spin when close to the ground.
Definitely not a standard manoeuvre now, is it?
S-turns might be taught as a way to lose a lot of height rapidly to correct an overshooting FLWOP, but the student must ALWAYS be made aware of the risks involved due to reducing IAS (due increased drag) and increased load factor.
Geez, I did my ab initio in a C150 from an airfield 3,500 feet AMSL
To any students who want to do a 40 deg turn into base as normal procedure, I hope your life insurance is paid up. That's bordering on a steep turn, not medium.
Extract from the FAA Airplane Flying Handbook - sub heading "Basic Flying Maneuvers"
For purposes of this discussion, turns are divided into three classes: shallow turns, medium turns, and steep turns.
* Shallow turns are those in which the bank (less than approximately 20°) is so shallow that the inherent lateral stability of the airplane is acting to level the wings unless some aileron is applied to maintain the bank.
* Medium turns are those resulting from a degree of bank (approximately 20° to 45°) at which the airplane remains at a constant bank.
* Steep turns are those resulting from a degree of bank (45° or more) at which the "overbanking tendency" of an airplane overcomes stability, and the bank increases unless aileron is applied to prevent it.
Buggered if I will teach students to use 40 deg Aob turns as a general course of action at low level. 15 is usually fine and 30 if required to tighten up the turn onto final.
If they need more than that, then they aren't anticipating enough or haven't read the wind correctly.
I didn't say it was a steep turn, just bordering on.
Quote the CASA Flight Instructor's Manual, Turning;
And that's the way every school I've taught at does it.
PS. None of them taught a 30deg climbing turn, either.
Again to quote the CASA Manual;
Unless you're flying at 200Kts, Rate 1 is a lot closer to 15deg than 30.
My point was that teaching a student to fly at excessive AoB's at low level in the early stages of their training might not be such a good idea.
If they need more than that, then they aren't anticipating enough or haven't read the wind correctly.
I didn't say it was a steep turn, just bordering on.
Quote the CASA Flight Instructor's Manual, Turning;
MEDIUM LEVEL TURNS
Definition A medium turn is one carried out with an angle
of bank of approximately 30 degrees.
Definition A medium turn is one carried out with an angle
of bank of approximately 30 degrees.
PS. None of them taught a 30deg climbing turn, either.
Again to quote the CASA Manual;
Point out that the angle of bank is restricted to only about a rate
one turn, otherwise the rate of climb is decreased markedly.
one turn, otherwise the rate of climb is decreased markedly.
My point was that teaching a student to fly at excessive AoB's at low level in the early stages of their training might not be such a good idea.
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Maybe SMS777 was onto something (other than something he ingested) with his omni directional runway idea. But it doesnt have to be as big as he desribes. What if we had assisted take off and arrested landing facilities much like those on an aircraft carrier? This would be particularly useful at city airports (formerly) GAAP as it would would release all that wasted land for the airport operators to sell off and make profits. Makes as much sense as ... helicopters.
15 degrees bank angle in the climb is normal in a trainer like a 150/152, pa28 or 172. 30 degrees whilst climbing just reduces climb performance and stall margin.
High wing aircraft need a good lookout prior to the turn. Performing a sudden eratic manuevre (like trying to turn suddenly onto crosswind or downwind) in front of another aircraft is far more dangerous. In the circuit the most important thing to remember is to be predictable. Following aircraft expect you to do a shallow climbing turn after take-off and they will manage their circuit to follow.
The rectangular circuit is much more appropriate in high density traffic environments as one can easily communicate position and visually sight other aircraft. The flow is predictable so lookout should be easier. An oval circuit requires more attention to just flying the circuit, less time available to look for traffic and more spent on alignment with the runway.
Airline manuals may depict a curved base in their manuals but inevitably most fly a square base to help judge the turn to final or separation with traffic. The curved path is more to keep the aircraft in the circling area with minimum chance of losing visual reference during such approaches.
40 degrees anywhere in the circuit is more an evasive manuevre than a normal one. Low speed with flap and a low experience pilot could easily overbank and get into trouble at low level, especially with disorientating wind conditions. If you tried this in a large aircraft it would yell at you annoyingly until the bank angle was under 35 degrees or so.
The longer you have one wing lowered in a high wing aircraft the more exposure you have to not seeing another aircraft in that blind spot.
The rectangular circuit is much more appropriate in high density traffic environments as one can easily communicate position and visually sight other aircraft. The flow is predictable so lookout should be easier. An oval circuit requires more attention to just flying the circuit, less time available to look for traffic and more spent on alignment with the runway.
Airline manuals may depict a curved base in their manuals but inevitably most fly a square base to help judge the turn to final or separation with traffic. The curved path is more to keep the aircraft in the circling area with minimum chance of losing visual reference during such approaches.
40 degrees anywhere in the circuit is more an evasive manuevre than a normal one. Low speed with flap and a low experience pilot could easily overbank and get into trouble at low level, especially with disorientating wind conditions. If you tried this in a large aircraft it would yell at you annoyingly until the bank angle was under 35 degrees or so.
Just doing some refresher training at "another" school. Very interesting.
In the circuit, sticklers for:
15 degree bank angle.
Always with enough height and speed for a glide approach to one of the runways (actually tested, and not on the duty runway either)
Always roll wings level before applying flap (pick up asymmetry if something breaks)
Always land full flaps.
Speeds base and final in a Warrior 80 KIAS, 75 KIAS Final, bleed back to 70 kias at fence. (less for short field of course). You are going to make the runway one way or the other.
Eyes to end of runway and try and fly there taught. Always land with full back stick, ideally with stall warning indication.
Maintain full back stick while braking.
Geeze I was getting sloppy before this.....
In the circuit, sticklers for:
15 degree bank angle.
Always with enough height and speed for a glide approach to one of the runways (actually tested, and not on the duty runway either)
Always roll wings level before applying flap (pick up asymmetry if something breaks)
Always land full flaps.
Speeds base and final in a Warrior 80 KIAS, 75 KIAS Final, bleed back to 70 kias at fence. (less for short field of course). You are going to make the runway one way or the other.
Eyes to end of runway and try and fly there taught. Always land with full back stick, ideally with stall warning indication.
Maintain full back stick while braking.
Geeze I was getting sloppy before this.....
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Always land full flaps.
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15 AoB climbing turn work fine and does not significantly diminish climb performance.
Other turns 30 AoB. you are very unlikely to stall from high Aob on base and final. you are much more likely to have issues if you use a shallow turn (or terrify poor luckless students that this is a maximum angle cos anything more is potentially 'dangerous').
A shallow turn, say 15 AoB, when added to a TWC on base means that the student may get pushed past the RW ECL and attempt to tighten the turn WITH RUDDER (cos more that 15 is dangerous remember). classic scenario. skid causes drag and sink, student raises nose to attempt to get picture right and treads a bit harder on the rudder, are you all following me?, there is a need to oppose the rudder with opposite aileron, so keeping low decelerating) wing up with aileron, nose starts to fall despite back pressure, low wing continues to descend despite full opposite aileron, ground getting closer, and closer faster, pull back really hard .........
15 works for oval but 30 is better for regular pattern, enabling sufficient time established with wings level to assess, adjust and confirm accurate position and approach profile.
Doing a 'derry turn' at circuit corners is fun but not for the pre solo student.
personally i like oval, but i do what is the 'normal' thing where ever i go. the "standard" pattern shape and altitude is there for a reason, not entirely sure what that is, but it does enable the instructor and student to determine if the standards specified in the instructional objectives are being met.
HD
Other turns 30 AoB. you are very unlikely to stall from high Aob on base and final. you are much more likely to have issues if you use a shallow turn (or terrify poor luckless students that this is a maximum angle cos anything more is potentially 'dangerous').
A shallow turn, say 15 AoB, when added to a TWC on base means that the student may get pushed past the RW ECL and attempt to tighten the turn WITH RUDDER (cos more that 15 is dangerous remember). classic scenario. skid causes drag and sink, student raises nose to attempt to get picture right and treads a bit harder on the rudder, are you all following me?, there is a need to oppose the rudder with opposite aileron, so keeping low decelerating) wing up with aileron, nose starts to fall despite back pressure, low wing continues to descend despite full opposite aileron, ground getting closer, and closer faster, pull back really hard .........
15 works for oval but 30 is better for regular pattern, enabling sufficient time established with wings level to assess, adjust and confirm accurate position and approach profile.
Doing a 'derry turn' at circuit corners is fun but not for the pre solo student.
personally i like oval, but i do what is the 'normal' thing where ever i go. the "standard" pattern shape and altitude is there for a reason, not entirely sure what that is, but it does enable the instructor and student to determine if the standards specified in the instructional objectives are being met.
HD
Airline manuals may depict a curved base in their manuals but inevitably most fly a square base to help judge the turn to final
Also, any square basing that goes on will also make the circuit bigger/wider, as well as annoying the pax by 2 x 90° turns instead of one continuous one.
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Hi PPRuNe, im new to this but not to flying. Im really pleased to find another site worth visiting and particularly enjoying the Downunder threads.
Wouldn't that be a scream, i can imagine the punters now, loves it.
C'mon HarleyD, we get it but must you be such a douche about it?
How would an IFR approach work into a circular runway? Perhaps ILS on a swivel. Maybe if RWY lights and approach directions are designated manually by someone qualified on the aerodrome (obvious answer for zones is the tower) Regulated kind of like a change of circuit direction. Brings up all sorts of issues doesn't it.
On the side, i assume that was a circular, not "spherical" runway sms777. Maybe in that case aircraft should orbit at various distances from the landing globe slowly making their way closer to landing... or do they just fly into the globe?
Food for thought: I once belonged to an outfit whos CFI insisted on students turning through 110 at the end of the downwind to make the resultant 70deg turn onto final easier to judge. I trialled it for a while and students really did get the hang of things quicker.
And finally, **NO** to >30 AOB in the circuit. Especially if you're instructing ab-initio. Thats playing with fire.
What if we had assisted take off and arrested landing facilities
are you all following me?
What i mean is a spherical runway design
On the side, i assume that was a circular, not "spherical" runway sms777. Maybe in that case aircraft should orbit at various distances from the landing globe slowly making their way closer to landing... or do they just fly into the globe?
Food for thought: I once belonged to an outfit whos CFI insisted on students turning through 110 at the end of the downwind to make the resultant 70deg turn onto final easier to judge. I trialled it for a while and students really did get the hang of things quicker.
And finally, **NO** to >30 AOB in the circuit. Especially if you're instructing ab-initio. Thats playing with fire.
Reckon it requires greater skill & judgement to make the climbing 180 and descending 180 turns..... so,
Square for ab initio - thru solo - up to precautionary
Oval x low level circuits - before & as an aid to precautionary exercise. Also useful for teaching bad wx/low vis arrivals.
happy days
Square for ab initio - thru solo - up to precautionary
Oval x low level circuits - before & as an aid to precautionary exercise. Also useful for teaching bad wx/low vis arrivals.
happy days
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Reckon it requires greater skill & judgement to make the climbing 180 and descending 180 turns.....
In real life i have done many thousands more curved approached and departures than square cornered ones, so a it is am important skill that needs to be learned regardless of what type of flying the student will be doing later.
HD
