Why don't we normally teach IP joins?
 

The IP join is such a simple beast and yet it's rarely taught outside the military. I haven't noticed it in any of the usual flying training books (Thom, etc) and there isn't an appropriate R/T call published in CAP413. Does anyone have any views on why that might be?

My humble opinion is that straight-in approaches ought to be discouraged at uncontrolled airfields and be replaced by an IP join (to break onto the crosswind leg, or earlier if appropriate). The prime benefit is to give time to fit into the other traffic rather than b^&gering up the poor bod that you didn't see on base leg.

A standard R/T phrase would be needed, howsabout "finals to break"?

Comments, opinions, exocets?

I thought that the main reason for a run and break was to allow high-performance slippery warbirds to pull the G necessary to slow down in a reasonable distance. Not something you need to do in your average traumahawk.

I concur with the sentiment of banning straight in approaches at uncontrolled fields. Everyone should be joining via the standard overhead join, then there'd definitely be no ******ing up of the guy on base.

cheers!
foggy.

One of the reasons may be that the IP join is in close proximity to the instrument approach path which might cause a problem but I agree it seems quite a hassle free procedure.

Bit slow here but what exactly is the 'IP' join? Sounds to me like a crosswind join. Can someone elaborate please. HFD, you say its to break into crosswind or earlier if appropriate, well if it is what I think then joining earlier if appropriate is a recipe for cutting people up you had not seen. Why not stick to the same profile regardless. At least we all know were to see you coming from. Does sound like another excuse for a split a**e run and break for the hell of it in a howling Bulldog at full chat. Correct me if I'm wrong please.

CAP,
The IP (aka STANDARD) join is a good and safe way to fit into the circuit if you happen to be at a point where you might elect for a straight-in (boo-hiss) approach. Start at a point on extended final (2 miles'ish), slightly on the dead side, run parallel to the rwy at circuit height and break onto crosswind at a point to fit-in with other circuit traffic.
I'll draw you a picture next time you're back from the colonies :D

The IP stands for "Initial and Pitch" - as in fly the initial leg of a circuit, then bank the aircraft and pitch onto the downwind in a constant turn. In it's simplest form it is basically an upwind join.

It is designed to allow a flight to maintin their formation to the circuit, then space the individual elements out for separate landings.

In the "old piston days" in Europe, it allowed an aircraft to maintain energy right to the airfield, then rapidly bleed that energy off in a high G turn onto downwind for landing - giving minimum exposure to the low energy state where the aircraft is most vulnerable to attack.

Neither situation really applies to civil operations, where flexibility in entering the circuit is more important and efficient in handling traffic.

That doesn't mean that it isn't fun though :D

[ 13 November 2001: Message edited by: Checkboard ]

Cheers HFD. I understand now. However, to me this sort of join at an uncontrolled civi airfield is dodgy. Take that satellite RAF run airfield south of EGDM. (Hehe) It has a lot of none radio traffic that will be expecting others to join into the circuit crosswind at crosswind height over the upwind numbers. If you join how you say, you could end up joinin at any point cos you you could assume that as you can't see anyone downwind, there ain't anyone there. End up pulling steep turn with your back side to the Piper Cub thats minding its own business downwind. This is why we should stick to standard joins as already taught. You IP is for military and controlled airfields were RT is mandatory. PS I should be back in real civilization for the Xmas dinner. No food fights tho please, I now have a reputation? (Do I????)
May well be back for the Mexican on the 17th to!! Bye for now, off to do raw data ILS's into London City now. Like doing the MEP(L) IR test again!

Checkerboard,

Ta muchly for the explanation, that's cleared up a lot of confusion on my part. As a civvy(ish) instructor teaching JAR PPLs at a RAF base we have all sorts of problems when the UAS come to visit. Of course they like their "initials" join but we don't teach it and this can cause conflictions in the circuit (I of course apologise most humbly and profusely to all the CFS instructors for even daring to occupy the same airspace as them).

The procedure seems sound to me and certainly less laborious than the overhead join but I do think it would be dodgy in an uncontrolled enviroment (although the Americans have their own variation at Unicom fields i.e. the join on the '45). Another problem arises because I have heard different people give different explanations of where they think "initials" actually is.

CAP,
Having recently had a near miss (according to the other bod - I didn't even see the b^&*er) during an overhead join I'm an even bigger fan of IP joins.
The big advantage is that you can see all the other traffic because you're running in straight for the last couple of miles.
My recent near miss seems to have come because we had both done overhead joins and the continuous turn to crosswind resulted in the other bod being in a blind spot. I thought I'd looked really well but it was dusk and he didn't have any lights (I had Nav and strobes on), my stude was yakking and I didn't hear the other bods R/T calls!
Confessional over.

OK, but if you are non radio, how do you work out which runway to set up the IP join for? With overhead join you look both for other traffic AND at the signals square, which you CAN'T look at on an IP join until to late. (And if you are not non radio you should be able to do a non standard join anyway at most fields).

[ 15 November 2001: Message edited by: foxmoth ]

Quite right - the overhead join is appropriate for non-radio aerodromes and the IP join is OK for aerodromes with people flying in a 'predictable' manner and with full RT. A low level join where you look UP at other traffic above the horizon before flying a climbing break when clear is even better in such environments. This will, however, mean that you couldn't have more than about 4 or 5 aircraft in the visual circuit at once. I regrettably conclude that, with the wide cross-section of skills displayed by the civil GA fraternity, the IP join is not generally appropriate.

But neither are those halfway-to-Heathrow cross-country navigation exercises flown by many pilots at White Waltham, for example.......

I used to love running break joins in Bulldogs.

But they are not appropriate in general GA use. I concluded that a year or so back as I gazed upon the North Weald Yak remains in the AAIB hangar. The mid air impact speed was estimated by the AAIB boffin to be 160kts. The Yak was performing doubtless a spiffing IP join and at least he went out with a smile on his face.

My sympathy lies with the poor ****** on downwind that he hit.

Nuff said really.

WWW

I know exactly what you mean. For those who don't know, circuit diagrams for White Waltham are available free of charge from operations and are also on their website at http://www.wlac.co.uk

--Mik