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Pace 26th May 2015 12:10

Circuit Procedures
 
Mary

i totally agree with you on the antiquated and out of date over head join.

It harps back to the days of non radio aircraft with minimal navigation equipment who needed to go over head and were pure VFR with minimal navigation aids

Firstly to be sure they were in the right place, to view the runways and read the signal square and look at the wind sock.

For me the OH join increases collision risk mixing high wing and low wing aircraft all making blind 90 degree turns and all homing into one spot like honey bees over an airfield.

flying straight in why make up to six extra blind 90 degree turns to end up in the position you were already in? why make your PAX uncomfortable and why add needless time to an already expensive flight.

Why mix fast and slow high and low wing together? its all a collision risk?

Very few aircraft do not have GPS and accurate DME readouts. so many of our regulations are still stuck in by gone eras which are not relevant today.

I too had to take avoiding action when an aircraft attempted an OH joint at 1200 feet with a 1400 foot cloud base cutting through the down wind leg :ugh:

Oh well the wheels of aviation turn very slowly and are stuck in the past

Pace

Dont Hang Up 26th May 2015 12:55


..seems to me that it is satisfying after takeoff to climb out at max power....if you have power to spare! Except they have these daft rules in the Uk of the overhead join! so just when my Supercub 150 is reaching circuit height when halfway along the runway heading, I remember that o dear me, there may be some numptie doing the overhead join and we will meet and make a mess on the runway....So nose down and behave, Mary! and sure enough, the other guy tools across just overhead...
Sorry but I have to disagree about the overhead join. It is a recognised manouevre that is more or less essential for a non-radio join, but is also efficient and disciplined no-matter what equipment you have. It is also the place where there should be minimum traffic so long as one has taken the trouble to check the field is not active for parachute jumping or the like.

And while it remains a recognised joining manouevre, then if you happen to meet someone coming up the way in a super-performing sports job then I am not quite sure who counts as the numptie.

DeltaV 27th May 2015 18:52


Sorry but I have to disagree about the overhead join.
I disagree too. I like the overhead join and don't really understand why people here seem to hate it so. Perhaps I fly to less traffic dense strips.

Pace 29th May 2015 07:40

70% of all midair collisions occur in and around the airport. I could be heading 360 to land on runway 36 at a given airport. with the OH I would need to complete six 90 degree turns just to get back to where I was!

That is madness in terms of time, cost, pax comfort , extra collision potential. I maybe in a high wing aircraft mixing with low wing aircraft all making these 90 degree turns and all homing in onto one spot above the airfield.

Also consider the OH join is supposed to be at 2000 feet and with the VFR vertically clear of clouds means the OH join can only be legally flown with a cloud base of 2500 to 3000 feet a rare occurrence in our climate .

That is most certainly abused with pilots scud running just below the cloud base way below those stipulations and sometimes even cutting across the downwind circuit height

For me at best it has a limited place but more likely its an out of date method more relevant to a by gone era of non radio aircraft with limited navigation ability

If the OH was so brilliant many other countries would use it but don't


Pace

Dont Hang Up 29th May 2015 11:00


70% of all midair collisions occur in and around the airport. I could be heading 360 to land on runway 36 at a given airport. with the OH I would need to complete six 90 degree turns just to get back to where I was!
No one is suggesting that an arrival on the runway heading should not do a long-final straight-in approach, or even join downwind if coming from the other direction. However this presumes a) you are familiar with the airfield and visual cues for the circuit and b) you have a radio and have determined the runway direction.

If you are unfamiliar with an airfield or its surroundings then I would always recommend the overhead join as the best way to orient oneself whilst still above the circuit traffic. Be honest, no-matter how hard you study the plates in advance the layout is never quite as you imagined it.

And frankly, if arriving on the deadside I am not sure what joining technique would work better than the overhead join! A lengthy detour onto long-final? An even lengthier detour onto downwind, whilst steering clear of departing traffic? And surely not descending from above into some indeterminate part of the active circuit! No - a smooth descending orbit overhead, with the final crossing of the active-runway over the depart-threshold at 1500ft to join the circuit downwind at co-altitude and at a precisley defined point (abeam depart-threshold). That for me is the safest and most efficient way.

Yes anyone trying to do it with less than 2000ft ceiling is (to use Mary's word) a numptie. But you can be one of those with any joining technique.

Of course I am only talking to pilots who take the "V" in VFR seriously. Those who consider even the most glorious CAVOK flight is an exercise in GPS programming are probably baffled by everything I have just said. :ok:

Pilot DAR 29th May 2015 14:57

Circuit Procedures
 
I have brought over the discussion of overhead joins to this new thread, so the discussion about steep climbouts can continue in parallel in its original thread....

Maccyboy 30th May 2015 05:14

Before completing my GFPT, I had been taught only mid-field crosswind joins, that is, overhead joins. Inbound on my GFPT flight test, my assessor, who was not my instructor, asked me to join the circuit "downwind". Sudden panic! Thank goodness I remembered join angle etc. Ended up a tight circuit but bluffed my way through. I was mad that my instructor had never got me to perform any other type of join other than mid-field crosswind. Nowdays though, flying at a small country strip, I'll always join mid-field crosswind because, to me, it gives me a good view of the windsock/s and the strip and gives me a couple of minutes to settle into the circuit.

ChickenHouse 30th May 2015 13:57

OH joins are nice where common, but dangerous where not!

Flying in the UK at an airfield where NORDO is common, it is very handy and used with the necessary precaution the best way to get in.
Flying the same procedure even after just crossing the channel may be hazardous, as gliders tend to use the dead side and parachuters may drop in the middle.
Flying OH joins in Africa? Usually a NoGo, we go low approach for lookout and animal chasing.

9 lives 30th May 2015 15:15

Though I'm not totally against overhead joins, and do them as local custom dictates, I avoid them if I can. To me, they are a mixing place where aircraft could be approaching the same point from different altitudes, and turns may be involved. I would rather not be there.

I would rather be straight in to some appropriate part of the circuit - which at a very quiet aerodrome might be straight in, following a good listen and look. Because, yes, I've had to chase animals off too!

Pace 30th May 2015 17:52

ST

I too am not against them if the cloud base is 2500 feet agl and visibility over a set minima.

Where I do disagree in the OH join being a standard join method there are direct joins which maybe more appropriate in lower cloud bases at circuit height.

The OH is abused with pilots attempting to join overhead near cloud bases and often way below the OH join heights AGL.

I am also concerned with the numerous blind turns themselves a collision risk.
so while I still feel there is a place for these joins I don't agree with the STANDARD part

Pace

TheiC 30th May 2015 21:26

Pace,

Pardon my asking... Where does the 70% figure come from?

Cheers.

Gertrude the Wombat 30th May 2015 22:16


And while it remains a recognised joining manouevre, then if you happen to meet someone coming up the way in a super-performing sports job then I am not quite sure who counts as the numptie.
I've had ATC hold an airliner on the runway until I (making an OHJ) was clear of his take-off path. Would it be reasonable to hope/expect ATC to be aware of the performance of a "super-performing sports job" and take similar precautions?


That is most certainly abused with pilots scud running just below the cloud base way below those stipulations and sometimes even cutting across the downwind circuit height
Surely if you can't make 2,000' you can't do an OHJ and have to join in some other way?

fireflybob 30th May 2015 22:36

Where is the statistical data that the OHP join is less "safe".

During training pilots should have been taught to avoid the live side when the cloudbase is such that an OHP cannot safely be conducted.

Pace 30th May 2015 23:32


78 percent of the midair collisions that occurred around the traffic pattern happened at nontowered airports.
This is from an AOPA report which is higher than the earlier study I googled. It does not refer to OH joins but surely any join which involves the honeybee effect of joining at a specific point in the OH plus up to 6 needless 90 degree turns mixing high and low wing aircraft MUST indicate a higher collision risk

On the reverse side of the coin it must mean that any joining procedure which does not involve the honeybee effect and minimises the number of blind 90 degree turns of high and low wing aircraft must lower the collision chance

Pace

TheiC 31st May 2015 02:11

That's not the same as

70% of all midair collisions occur in and around the airport.

Pace 31st May 2015 06:20

Theic

I will have to re look up the link for the statistic that 70% of midair collisions happen in and around airports. its probably about right as its in and around airports that there is the greatest proximity of aircraft of all types and with that the greatest chance of a collision.

From a CAA report

c) A study of over two hundred reports of mid-air collisions in the US and Canada showed that they can occur in all phases of flight and at all altitudes. However, nearly all mid-air collisions occur in daylight and in excellent visual meteorological conditions, mostly at lower altitudes where most VFR flying is carried out. Because of the concentration of aircraft close to aerodromes, most collisions occurred near aerodromes
With the HoneyBee effect of the OH join and the multiple unneeded 90 degree turns that join has to increase the risk.

I probably have around 3000 hours in various piston twins and approaching an airfield with an overhead join would always position myself for a circuit height join usually straight in or downwind and request that. i considered mixing a fast twin with Cessna 150s and with all the blind turns was a risk factor electing instead to give final distance reports and communicating with down wind or base aircraft as a safer procedure.

Sometimes the join would be refused and you had to go overhead with the usual dead side descent and multiple turns but I always considered the risk factor as being higher, The turns a waste of time and money and those turns being uncomfortable for PAX. A relic of a bygone era.

Again the OH should be at 2000 in the OH not 1900 1800 1700 or lower which is often the case with cloud base restrictions and again often with aircraft scud running the base of those clouds and should you question the advisability of having everyone approach the same point at exactly 2000 feet?


Pace

Jumbo Driver 31st May 2015 12:59


Originally Posted by Pace (Post 8993250)
70% of all midair collisions occur in and around the airport. I could be heading 360 to land on runway 36 at a given airport. with the OH I would need to complete six 90 degree turns just to get back to where I was!

Not sure I follow your reasoning, Pace ... 6 x 90° = 540°, so you would then be landing on runway 18, would you not? The easiest way to join in this case would surely be to approach on the dead-side, descending to circuit height, then turn to join the circuit crosswind? (involving just 4 turns, just like any normal circuit.)

This subject really is an old chestnut. For those of us brought up some years ago, the default way to join a circuit was (and still is) by the Standard Overhead Join. Not only is it recognised practice but it separates joining/descending traffic and circuit traffic and, for established circuit traffic, it clearly defines where any joining traffic should appear. Obviously, for circuits where, for some reason, there is no dead-side or where alternative joining procedures are promulgated, or where there is ATC, an OHJ is neither suitable nor expected. But for a default procedure, where needed, I would suggest that it remains totally adequate.

The only comments I would add are that, firstly, overhead join should made at 1000' above circuit height - i.e. at 1800' for a circuit at 800'. Secondly, it must be infinitely better than the USA pattern joining procedure which involves a 45° turn against the circuit direction in the mid-field downwind position.

JD
:)

sapperkenno 31st May 2015 15:38


...it must be infinitely better than the USA pattern joining procedure which involves a 45° turn against the circuit direction in the mid-field downwind position.
If you think about it sensibly (have you ever flown in the U.S.?) it's a far better system, where you can survey the whole circuit as you approach, and been at the same height can generally spot traffic against the sky as opposed to looking down on it from an overhead join and then descending onto a position where there could be traffic.
Also, everyone knows where you are going to enter the pattern with the 45° system, as you said yourself it's the mid-point downwind. How is that difficult?

Pace 31st May 2015 18:17

JD

You approach to the OH turn to descend deadside 1 descend and make turn two to go to the crosswind 2 make another turn to run crosswind 3 make another turn to go down wind 4 make another turn to go base 5 and another to turn final 6 where you were in the first place with NO turns ;)

Broadlands 31st May 2015 20:46

I just wish those pilots who insist on a long final could be re-educated to fly an OH join and stop screwing up established circuit traffic.
OH joins rule!


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