Why do many "Airline" training organisations insist on flying such wide circuits?
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Ok thanks for that Checkboard
It's not 60, but 25 (Sydney, Melbourne and Adelaide have not ever, nor are likely to be, (barring global warming) in the "north and west of Australia" (and 6 of those have ILS's), but still a very respectable list.
Your claim of "still a lot of circuits" does not hold much water when what you were probably doing was maneuvering in the circling area after carrying out some form of instrument/dme arrival.
Not really what this thread on training school circuits was about, though.
It's not 60, but 25 (Sydney, Melbourne and Adelaide have not ever, nor are likely to be, (barring global warming) in the "north and west of Australia" (and 6 of those have ILS's), but still a very respectable list.
Your claim of "still a lot of circuits" does not hold much water when what you were probably doing was maneuvering in the circling area after carrying out some form of instrument/dme arrival.
Not really what this thread on training school circuits was about, though.
Easiest picture I could find of a standard circuit is here
God help the poor newbies who listen to all this sooking about curved this and curved that. There are 5 legs to a standard circuit pattern and they are all straight and perpendicular to the previous leg. How you fly it is your business.
God help the poor newbies who listen to all this sooking about curved this and curved that. There are 5 legs to a standard circuit pattern and they are all straight and perpendicular to the previous leg. How you fly it is your business.
Not necessarily so!
Part of the problem, I think, is that the rules keep changing! For the first 15 years or so of my flying things were pretty much stable and most of us knew what we were doing. Then the inmates were put in charge of the nut house and most of us struggle to keep up with the changes.
Two things came out of my last "workover" with a very, very, very experienced senior instructor and ATO.
1) My nice square turn onto cross wind after TO is out and "a continuous rate one climbing turn onto downwind" is in, and
2) When joining overhead, flying crosswind over the downwind threshold is out, and crossing mid-runway to join mid-downwind is in.
My answer to all this? Keep my eyes peeled out the window and make it up as I go along. Seems to work OK as I flew into YCAB about five times before I figured out that it was RH circuits onto Rwy 30.
Dr
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Hello Dr,
The 'racetrack' turn to downwind you described, is as taught by Ando and his cohorts and described earlier in this thread. I've also noticed the very military terms 'High Key and Low Key' appearing in CASA's Visual Pilot Guides as well. Maybe the oval circuit as taught at BFTS is the future.
What the law says about the circuit pattern
The answer to what should be a simple question is?????
The 'racetrack' turn to downwind you described, is as taught by Ando and his cohorts and described earlier in this thread. I've also noticed the very military terms 'High Key and Low Key' appearing in CASA's Visual Pilot Guides as well. Maybe the oval circuit as taught at BFTS is the future.
What the law says about the circuit pattern
The circuit pattern consists of five flight legs, each of which involves a series of standard procedures and manoeuvres used to allow the safe and orderly flow of aircraft traffic into, around and from an aerodrome. The circuit procedures also safely expedite a number of take offs and landings to be practised in a short period of time. The circuit is a series of events beginning with the preparation for take-off and culminating in a stable approach and landing.
The operational practices that are covered by the regulation are those general requirements with which the pilot-in-command of an aircraft will be required to conform when approaching a non-controlled aerodrome for a landing and when joining or departing the air traffic circuit.
A penalty of 25 penalty units applies for non-compliance with the subregulation. The offence is an offence of strict liability. One penalty unit is currently set at $110 under the Crimes Act 1914.
The operational practices that are covered by the regulation are those general requirements with which the pilot-in-command of an aircraft will be required to conform when approaching a non-controlled aerodrome for a landing and when joining or departing the air traffic circuit.
A penalty of 25 penalty units applies for non-compliance with the subregulation. The offence is an offence of strict liability. One penalty unit is currently set at $110 under the Crimes Act 1914.
Last edited by Back Seat Driver; 20th Jan 2010 at 05:18.
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and "a continuous rate one climbing turn onto downwind" is in,
The Rate One climbing turn harks from the old days in Tiger Moths where a circling climb to height prior setting course for a cross-country from over the field, was best done at Rate One in order to get to height more quickly that a continuous steep turn over the field over a smaller radius. Nothing wrong at all with a 30-35 degree angle of bank turn for the first crosswind leg -straighten up for a few seconds for spacing and a good look around, then same bank angle on to downwind. Same on base and final.
Aviast, Paul Bertorelli is pure gold....like his instructor shirt with multiplying gold bars...looks like the US runs into the same problems as we do here.
......Often wonderd about circs at PC...should you have to wear a life jacket?
......Often wonderd about circs at PC...should you have to wear a life jacket?
That was a funny clip, but I'm not too sure about his advise on slipping to get down, sure it is a useful skill to have but side slipping near the ground for most students should be a big no no (unless of course they are flying an aircraft that uses sideslips to control descent) If we teach students to side slip down final all the time then when they start taking paying pax up they will be plastered to the side window.
Yes I think students are flying larger circuits then needed but there is also a point where the circuits can get a little too close, (if you fly AG ignore all of this, it is in no way aimed at you). Turning final at less than 500ft is unnecessary at most airports (there are always exceptions) it invites error and leaves little room for inexperienced pilots. On the other hand turning final at 1000ft is also unnecessary (unless you're trying to demonstrate something to a student) and shows poor airmanship. In a standard light single your final and base speed will be appx. 60-70kts, so to be at 500ft as you roll wings level on final should have you about 1.5nm from touchdown (standard 3deg profile).
Yes I think students are flying larger circuits then needed but there is also a point where the circuits can get a little too close, (if you fly AG ignore all of this, it is in no way aimed at you). Turning final at less than 500ft is unnecessary at most airports (there are always exceptions) it invites error and leaves little room for inexperienced pilots. On the other hand turning final at 1000ft is also unnecessary (unless you're trying to demonstrate something to a student) and shows poor airmanship. In a standard light single your final and base speed will be appx. 60-70kts, so to be at 500ft as you roll wings level on final should have you about 1.5nm from touchdown (standard 3deg profile).
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@Aviast
Thanks for the picture you posted
In a downwind you are at a horizontal distance of approximately 6000 feet from the runway, and vertically about 1000 ft above runway. An observer at the runway will see your aircraft at an elevation of 10 degrees. ( 100 feet height over one NM subtends 1 degree arc)
Which means that the observer on runway should raise his eyesight 10 degrees above horizon to sight you. In the same manner you should see the observer 10 degrees below horizon from your left window.
In order that this 10 degree line of sight to pass through "half wing strut" and pilots eye, the pilot's eye must be at the same level as the glare shield. You can do this small exercise using a protractor and 3 plane view in the manual.
As you maintained that you did these circuits with "Half-wing-strut", the only way to accommodate a comfortable eye hight and the 1.02 NM wide downwind leg is by flying at 1500 AGL instead of normal 1000 AGL.
Usually the half wing strut method gives a width of 3/4 statute miles or 4000 feet approx. While in your case it gave a width of 1 NM, i.e. 6000 ft. Which led me to think there must be something wrong, but still you have managed fairly consistent widths, Is it possible that you were using any landmark other than the runway itself? My primary instructor emphasized that I should be able to do the pattern with reference to the runway, the aircraft and nothing else.
In my opinion safe distance from runway for single engine piston aircrafts is no more than 4 times the pattern height above ground. Then instead of 10 degrees it ought to be 15 degrees elevation.
One of the foremost consideration in designating such relation is the scenario of power loss in pattern. Just from how far can a trainee pilot safely land at airport in case of an emergency? We must take into account, representative glide ratio, adverse winds and low time pilot.
Any one trying to maintain wider than 3/4 sm in SE Piston is a safety hazard. There are several schools especially outside USA which recommend patterns as wide as 1nm to 1.5nm for SE Piston. I have never understood why they do so?
In a downwind you are at a horizontal distance of approximately 6000 feet from the runway, and vertically about 1000 ft above runway. An observer at the runway will see your aircraft at an elevation of 10 degrees. ( 100 feet height over one NM subtends 1 degree arc)
Which means that the observer on runway should raise his eyesight 10 degrees above horizon to sight you. In the same manner you should see the observer 10 degrees below horizon from your left window.
In order that this 10 degree line of sight to pass through "half wing strut" and pilots eye, the pilot's eye must be at the same level as the glare shield. You can do this small exercise using a protractor and 3 plane view in the manual.
As you maintained that you did these circuits with "Half-wing-strut", the only way to accommodate a comfortable eye hight and the 1.02 NM wide downwind leg is by flying at 1500 AGL instead of normal 1000 AGL.
Usually the half wing strut method gives a width of 3/4 statute miles or 4000 feet approx. While in your case it gave a width of 1 NM, i.e. 6000 ft. Which led me to think there must be something wrong, but still you have managed fairly consistent widths, Is it possible that you were using any landmark other than the runway itself? My primary instructor emphasized that I should be able to do the pattern with reference to the runway, the aircraft and nothing else.
In my opinion safe distance from runway for single engine piston aircrafts is no more than 4 times the pattern height above ground. Then instead of 10 degrees it ought to be 15 degrees elevation.
One of the foremost consideration in designating such relation is the scenario of power loss in pattern. Just from how far can a trainee pilot safely land at airport in case of an emergency? We must take into account, representative glide ratio, adverse winds and low time pilot.
Any one trying to maintain wider than 3/4 sm in SE Piston is a safety hazard. There are several schools especially outside USA which recommend patterns as wide as 1nm to 1.5nm for SE Piston. I have never understood why they do so?
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A few years ago, an instructor commenting on this issue at Jandakot, reckoned a certain foreign school used circuits as nav. exercises, such was the distance from the field.
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so to be at 500ft as you roll wings level on final should have you about 1.5nm from touchdown (standard 3deg profile)
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Two points from me.
First, it is unlikely you'll safely make the runway in the case of power loss mid-downwind, no matter what your spacing. You might physically reach the runway you've just departed from, but you're pretty sure of running off the end (unless you happen to be training at Edwards AFB). Much more achievable is a turnback from ~500+ feet AGL after takeoff, or through crosswind, or early downwind. From mid-downwind onwards, on a regular training circuit you just won't make the runway. (There's a narrow window just before base turn, but that's discounted in this discussion as it's a highly unlikely scenario).
So we can discount trying to make the runway as a factor in circuit design. This brings me to my...
Second point. The primary reason for flying circuits is to give a student pilot the opportunity to practice takeoff, approach, and landing. Therefore, the circuit should maximize the student's training value, by being as efficient as possible while coonsidering the aircraft's performance characteristics. As student ability changes, so should the manner in which the circuit is taught/flown. In my opinion, the oval circuit is better, as it challenges judgment and assessment in ways the square pattern cannot, and it copes better with changing wind conditions.
First, it is unlikely you'll safely make the runway in the case of power loss mid-downwind, no matter what your spacing. You might physically reach the runway you've just departed from, but you're pretty sure of running off the end (unless you happen to be training at Edwards AFB). Much more achievable is a turnback from ~500+ feet AGL after takeoff, or through crosswind, or early downwind. From mid-downwind onwards, on a regular training circuit you just won't make the runway. (There's a narrow window just before base turn, but that's discounted in this discussion as it's a highly unlikely scenario).
So we can discount trying to make the runway as a factor in circuit design. This brings me to my...
Second point. The primary reason for flying circuits is to give a student pilot the opportunity to practice takeoff, approach, and landing. Therefore, the circuit should maximize the student's training value, by being as efficient as possible while coonsidering the aircraft's performance characteristics. As student ability changes, so should the manner in which the circuit is taught/flown. In my opinion, the oval circuit is better, as it challenges judgment and assessment in ways the square pattern cannot, and it copes better with changing wind conditions.
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First, it is unlikely you'll safely make the runway in the case of power loss mid-downwind, no matter what your spacing.
Isn't power of 180 landing a part of FAA commercial pilot practical test standards for ASEL, which all CPL applicant have to demonstrate.
The applicant must land the aircraft within 200 feet of a point on runway abeam the point in downwind where the engine failed.
If one can do it at the end of the runway, you can do it at the middle of the runway.
Millions of pilots have demonstrated and passed the Power of 180 accuracy landing from traffic pattern.
it is unlikely you'll safely make the runway in the case of power loss mid-downwind
You might physically reach the runway you've just departed from, but you're pretty sure of running off the end
Dr
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so to be at 500ft as you roll wings level on final should have you about 1.5nm from touchdown (standard 3deg profile).
Of course you can drag a Cessna 150 in with full flap on a estimated three degree glide slope but you will need considerable power to keep the speed up. The normal approach angle for a light single with landing flap, 60-70 knots and 1200 to 1500 rpm is more like five or six degrees and perfectly comfortable. Try flying a PAPI or ILS in a Cessna 150 or Warrior and you will soon discover that significant power is needed to make such a relatively shallow approach if flap is full down.
A three degree approach at 65 knots ground speed gives a rate of descent of 325 feet per minute. Try a 15 knot headwind component and the rate of descent reduces further to 250 fpm. 250 fpm in a Warrior with full flap means an awful lot of power. That means from 500 ft on final it takes you two minutes to the flare. For 140 knots airspeed the rate of descent is around 700 fpm which is omfortable for a 737/A320 allowing for inertia in the flare.
Aiming for a "standard" three degree glide path profile in light aircraft is impractical and unnecessary.
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Tee Emm,
that's why I keep the 210 at 140 knots til just under a mile...
(in all seriousness though, I agree - no one could argue that the half-screen attitude taught for final approach in baby cessnas results in three degrees...)
Go down hard, or go fast!
that's why I keep the 210 at 140 knots til just under a mile...
(in all seriousness though, I agree - no one could argue that the half-screen attitude taught for final approach in baby cessnas results in three degrees...)
Go down hard, or go fast!
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Because when you fly at places like Point Cook where the clowns from the school down there have 6-7 planes in the circuit at a time you need to space yourself out. But for some reason this is beyond their comprehension and they continue to do short finals and go arounds without getting any actual useful practice in. Use your common sense......
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there are few flying colleges that flies light aircraft down a 3 degree profile, not the usual 4, for most light aircraft. This means that downwind (and base) is extended slightly, so as to prevent an excessive ROD on base/final. The result is a bigger circuit.