1500ft circuits
 

I'm curious to know what people think of the recently introduced changes(relatively) to circuit heights for "high performance" aircraft.

Generally, I have found that most have not adopted to the 1500' cct ht and continue to fly 1000' ccts. I personally fly a 1500' cct, but prefer the shorter and quicker 1000' cct when I'm flying at about 140kt.

I reckon the new laws were introduced to provide better conflict resolution between faster and slower aircraft in the circuit area, but I have not once overflown and overtaken another aircraft in a circuit.

How do you fly your circuits? Do you extend your downwind to drop the extra 500'? Do you accept a larger rate of descent within the same downwind leg of the 1000' circuit? Do you slow down to 120kt? Have your companies SOP changed to reflect the new legislation? How do the military teach it?

The legislation from the AIP enroute (25may08) is shown below

57.3 Circuit Height
57.3.1 When operating at non−towered aerodromes, the following circuit
heights are recommended:
a. jets/turbo props/high performance aircraft, 1500FT AGL;
b. typically single engine piston, 1000FT AGL;
c. ultralights with a maximum speed of 55KTS and
helicopters, 500FT AGL.
NOTE: High performance aircraft are those that have a normal
downwind speed of greater than 120 knots.

I hate them but for selfish reasons, I can't stand making circuits any bigger than they need to be and they just feel to me too high/large to be practical.

Newly adopted ??????????? how so, 1500 has been thus as long as I can remember for high performance aircraft.

Forkair SOPs call for tight circuits. For what its worth, I extend the downwind leg to allow for the additional 500'.

Dr :8

Yep, been around a long time.
As to how sensible it is; not very, in my view - having aircraft doing circuits at different heights just increases the chance of someone descending on top of someone else, I reckon.
Probably why nobody does it.
In reality, most of your so-called high performance aircraft would be coming off instrument approaches, or visual approaches under tower instructions, so the 1500 ft rectangular circuit thing isn't going to be relevant anyhow.
OCTA, I can't imagine the 1500 ft circuit gets much of a look-in.

T28D - Perhaps I didn't realise the clause earlier when I was flying slower aircraft, or CASA defined high performance aircraft as aircraft that fly >120kt ccts.

I also fly tight ccts but instead of extending downwind, I drop full flap and accept a larger RoD. Although the flaps in the piston acft that i fly most allows for this since they are hydraulically actuated and if both engines fail (read: hydraulic pumps fail) they will retract with the airflow provided I pull the electrical hyd pump ccb. People on the ground always make comments on "how high were you on downwind?" etc But i dont like extending the cct to more than it needs to be.

The result for me is that I cant get a good short cct that im comfortable with. Are today's instructors teaching larger ccts in these " high performance " acft? Does anybody expect a light twin to be at 1500' on downwind? How many people have changed their flying technique to suit 1500' rule? I have but I dont like it.

The 737s in Broome fly 1500' circuits, but its never a problem for traffic.

I'd consider that to be a relatively high performance aircraft, but do light twins really count?

I am holding my breath for the first "airprox" that occurs when an a/c does a 1500' circuit at Camden whilst another a/c reports inbound at 2RN at 1500'....


if it ain't broke... don't fix it (or f*ck with it)

Can anyone point me to the reference for circuit height at a towered aerodrome please.

As long as I have been involved in aviation it has always been 1500 ft CCTS for high performance A/C?? To my knowledge not many regional airlines adopt the 1500ft ccts at CTAFs . Try following a metro at night into YSBK, The tower asks for speed reduction for both A/C at prospect. I can never seem to keep up:sad: They dump the gear and flap and fly a tight base and final. No need for 1500 Ft ccts maybe just for the jets, even the smaller citations and Learjet’s seem to manage fine with 1000ft ccts.:ok:

Maybe a few Light jet and turbo prop drivers can shed some light???

No way Jose!

I'll stick with extending downwind rather than descend on the downwind leg.

Dr :8

"The legislation from the AIP enroute (25may08) is shown below

57.3 Circuit Height
57.3.1 When operating at non−towered aerodromes, the following circuit
heights are recommended:
a. jets/turbo props/high performance aircraft, 1500FT AGL;
b. typically single engine piston, 1000FT AGL;
c. ultralights with a maximum speed of 55KTS and
helicopters, 500FT AGL.
NOTE: High performance aircraft are those that have a normal
downwind speed of greater than 120 knots."


Theres the critical word in that paragraph. "recommended"!!!!

So if the pilots that are not flying at the 'recommended' circuit altitudes have in fact read this chapter in AIP/Jepp then they are obviously taking the word recommended quite literally. Or they just havent read this and are just flying at 1000' as per the old days.

I brought this exact subject up last year & am happy to see it's back on the agender.
'Pas' yes what you say would be a simple way of dealing with the extra height, start down on say late downwind, abeam the ldg thresshold drop gear & head on down (typical), that's exactly what I/we do to avoid high ROD's.

'airman1' yr right there mate 1500' cts have been in place since Noah took up flying, well for jet types anyway. I believe they brought them in for high perfomance 'anything' because most slippery types fly downwind at say 130-150 kts anyway, LR35 for Eg.

'htb' also correct the whole procedures are 'recomended' as you have highlighted I think mainly because 1500' may not be possible wx wise but still legal visually for ldg.

Like I said once before healthy debate is good:ok:


CW

Young Wally...... Was just about to page you I could smell the debate brewing at post 3. So in the lovely king air you always fly a 1000ft cct and just extent the downwind?? Good thing you have two engines wouldn’t want to go extending the downwind too much in a single (lets say a PC12) you mighten make the keys in an engine failure!!! :ok:

Hirethebetter, your dead right recommended is the key word there!!!

I just wonder how many drivers get lazy and let down on downwind earlier?? (None that would ever admit to it anyway):ugh:

Oh Brother! Not that crock of sh*t again!

The L35's a bit of a slug in the circuit, huh Wally? I used to fly the FTDK downwind at 140 kts until dropping the gear out opposite the threshold.

Dr :8

PS: Why doesn't someone do a bit of research and post a few crash reports on SE aircraft that have suffered engine failures on the base or final approach leg of the circuit - due to other than fuel starvation!

FTDK - don't get all wound up - airman has probably never flown a PC12 or Bo

Desert Duck/Forkt don’t get your knickers in a knot, just stirring the pot!! And yes have over 50 Hrs in the PC 12 logged in the book. Lovely piece of gear but it definitely has its place in the industry like capt Wally has always said. :ok:

Sorry for the thread drift continue.......

It all makes sense when you fly a Category C machine in a cct in VFR/IFR situations.
When in VFR a 1500' cct is perfect. And you are following the local VFR rules..ie left or right hand ccts. In total, cct times are similar for all categories as a result.
In a circling approach (following an IFR instrument approach)(in a cct) max speed is 180kts and then you know that you are the only one doing the cct, so therefore do either left or right hand cct, whatever suits-you-sir. You just need to maintain obstacle clearance (400' for cat C) till on approach path/angle for the runway which could be as early as on an oblique downwind. These ccts are usually done at about 1000' and are limit by visibility.
Sorry to be so tech but it all works nicely.

:)

Day or night as the PIC you have to guarantee obstacle clearance.
Its in the regs my friend.

TTT,

I can understand the rules' application to a faster CAT C acft but how about a fast CAT B? Without descending on downwind, which i thinks contradicts the reason for the implamentation of the 1500' >120kt cct, the question becomes do you allow for a greater rate of decent and keep the cct tight, extend the downwind, or don't apply the recommended procedure altogether?