Overhead Join - a better way?
 

Not asking for pro's and con's of the OHJ - discussed too many times in too many forums.
Is there a real alternative method of arriving on the ground at an airfield that would meet most needs be a better standard procedure where special joins are not specifiedOHJ?

Well, Using one of my most recently familiar airfields..

Currently at Kemble, what with the increased activity due Brize "moving" to Fairford, procedures exist when there are ILS/PAR inbounds to Fairford on Rwy09, the extended centreline of which routes through Kemble's Overhead approx 1/2 mile north of the main Rwy.

When this is the case, the ATZ height drops to 1000' QFE and No Ohj's permitted, just Straight in's (offset due NA) or downwind/base/crosswind joins.

All this information is passed over the RTS, with no prior knowledge expected from visiting pilots. Apart from the noise abatement, which im sure everybody reads!

The American 45° downwind does it pretty well - it's easy to space into even quite a bust pattern.

The big advantage of OHJ in my mind however, is that it doesn't rely upon RT to tell you what the circuit direction is, plus allows a good look at the field before landing. Downwind does neither of those things, and even a deadside join only does the second.

G

I've put quite a bit of thought into this and the one thing you can't get away from is the initial observation of the runway and signal square.

The question asked if there would be a "better" join. I think that requirements vary so much from place to place, it's impossible to say what's "better" in a generic sense. For example, at Blackpool, the airfield I now fly out of, which has ATC, an overhead join is rarely "best", since it adds time to the flight unnecessarilly, and a base leg join is more normal, with slight variations to fit in with circuit traffic (such as joining at 1500', or positioning behind the downwind traffic). On the other hand, I learnt to fly at White Waltham, and I can't think of a "better" way of joining there than the standard overhead join. And if I owned my own farm strip which wasn't published anywhere so I could be reasonably confident no one else was in the circuit, I could do whatever type of join I wanted.

I can think of lots of alternatives which might be better where a radio is required, but I'm struggling to come up with a join which will work as well at busy non-radio airfields.

As Genghis says, the American 45° join works well in America (especially with the number of small GA fields that have parallel runways with oposite circuit directions over there, which immediately rules out an overhead join). But it's also worth pointing out that this join is not legal, since it involves, in a left-hand circuit for example, a right hand turn.

FFF
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Not legal?

Not recognised practice in the UK certainly, but illegal if local procedures decided to call for it?

G

Genghis,

Rules Of The Air, Section 4, rule 17, paragraph 5:For a left hand circuit, the 45° join (how do you get the ° sign without copying+pasting from your post?!) requires a right turn from the 45° leg onto the downwind leg, which goes against the above rule.

Degrees
 

Yes,how do you get the degree sign????
Lister:D:confused:

So, an AFIS or non-radio airfield with no signal square and a right hand circuit is illegal then. I can think of one or two.

To do a degree sign by the way, assuming you're using a conventional PC, hold down the left hand "Alt" key, then type 2-4-8 on the numeric keypad before releasing the Alt key. 2-5-3 is useful as well, giving ².

G

You could always cross midfield at pattern altitude and turn left into the downwind at 45 deg. This would satisfy a very very narrow interpretation of the 'no right hand turn' rule. It's also a standard method of entering the pattern if you arrive from the 'wrong direction'.

To determine landing runway. Cross overhead at pattern altitude + 500ft, and at a suitable distance from the airfield descend to pattern altitude in a right turn (for left traffic), and join downwind as normal. Descending to pattern altitude in the very near vicinity of the airfield is not a good idea, IMO.

There is another solution presented on Avweb which may or may not be superior to that in the standard AIM (not IMO), but is sure to confuse the heck out of other people expecting standard radio calls/traffic pattern flying.

I've always been uncomfortable with the idea of a 45deg join to downwind because it involves turning your belly to the oncoming traffic, but I guess US accident statistics would prove or disprove the apparent risk.

My preferred join is to fly parallel and close to the runway at circuit height, slightly on the deadside, and then to turn onto crosswind. It allows you to verify the runway and wind, see downwind traffic (and modify the crosswind turn accordingly, if necessary) and to arrange an efficient descent. A little lower than circuit height skylines the other aircraft.
(Note: no mention here of calling "initials" or VRIAB).

HFD

HFD,

That crosswind entry would 'expose your belly' to traffic joining the pattern via an extended downwind. I'm not saying your preferred pattern is a bad one, just that if you are at a non-towered airfield in the US, you can enter the pattern anywhere you want, or even just fly an extended final. See and avoid is key, you don't even have to have a radio, and can even land on the opposite end of the runway that everybody else is using. However if you had an accident I suspect the pattern in the AIM is the non careless and reckless one. Best to fly what everybody else expects.

SS: I guess that's true of any turn into the circuit/pattern but joining from Crosswind (either from an overhead join or from the join I described) you get to inspect the downwind leg from 90deg so it seems that you would be more certain of "who's where" than joining at 45 degrees.

HFD

Degrees etc
 

Genghis,many thanks for that
Lister:D

HFD,

Yes, the 90deg view is good to have, in fact the FAA now want to see proper wings-level legs in the PPL practical test so you get a 90deg view of the other legs. I guess every solution to flying close to an airport has potential failings, but I think the one suggested in the FAA AIM is better than others.

"My preferred join is to fly parallel and close to the runway at circuit height, slightly on the deadside, and then to turn onto crosswind. It allows you to verify the runway and wind, see downwind traffic (and modify the crosswind turn accordingly, if necessary) and to arrange an efficient descent. A little lower than circuit height skylines the other aircraft."

Works fine - that's a standard RAF join procedure! :ok:

ST:
absolutely! I don't understand why it isn't more widely taught in preference to straight-in approaches to uncontrolled fields?

HFD

You know of uncontrolled fields routinely recommending straight-in joins?

The deadside join is not uncommon (upwind join to Americans), but in my experience the straight-in certainly is, and should be.

G

OK, so you are joining at a field using the "American" join, there are 8 in the circuit with the downwind full and most remaining in the circuit doing T & Gs, where do you and the other joining a/c go until there is a suitable break - orbit away from the airfield and you could be in conflict with other aircraft doing the same thing - plus you cannot see WIHIH whilst you are turned away from the field.
At least with the OHJ you are orbiting above the field, all in the same direction, with other joining a/c in sight and you can see the circuit to judge where there may be a suitable gap to join.
It may not be perfect, but I still prefer it myself to the other methods when it is busy and you do not have positive control from the ground.:hmm:

I've only flown 40 hrs since getting my PPL but I'm already enjoying landing away at various airfields. I have found that the joins can vary widely, so a rule of thumb I have is always to speak to the location I'm planning to fly to in advance. That way I find out their preferred joining method and the reasons why, so I know how I'm going to approach the airfield long before I get there. I find this eases my in flight workload a good deal and I feel more confoident knowing what to look out for and expect.

p.s. this post probably sounds a bit obvious, but I know of plenty friends who don't bother asking about the join when getting PPR etc.