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Chris_S
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I'm nearing the end of a LAPL course and researching overhead joins as there are so many different opinions its not clear to me what the correct method is. It does seem unsafe to me if different people fly it differently.
From what I can tell, the skydemon function to help people into the circuit looks useful but it is not an overhead join, should the feature be renamed to 'Circuit Join' perhaps?
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Tony N
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Chris, I think the SD function is simply to position you in the, generally, correct location to conduct the type of join you have selected. You really shouldn't be looking at your SD device when in the circuit - maximum lookout required in that, potentially, busy aviation environment. I may quickly glance at my SD display to see if I am, more or less, following the necessary circuit path, especially at an airfield I haven't visited before, but that is about it! Tony
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Chris_S
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+xChris, I think the SD function is simply to position you in the, generally, correct location to conduct the type of join you have selected. You really shouldn't be looking at your SD device when in the circuit - maximum lookout required in that, potentially, busy aviation environment. I may quickly glance at my SD display to see if I am, more or less, following the necessary circuit path, especially at an airfield I haven't visited before, but that is about it! Tony Agree, I've never actually used SkyDemon in flight, I was just commenting on the confusion over what an overhead join is Vs what skydemon calls an overhead join ...
Chris
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grahamb
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Overhead joins are straightforward, but the CAA poster is misleading as it creates the impression that you can only join it from one direction.
The reality is that it’s a big roundabout in the sky, with a diameter slighter longer than the runway in use. You join it from any direction, always turning in the circuit direction, and keep going round until abeam the landing threshold when you start your dead side descent to be at circuit height as you go crosswind.
SkyDemon doesn’t depict all of that so it just gives you the final crosswind descent in the correct direction to a nominal circuit. It would be better if the nominal circuit bit was removed as it serves to confuse.
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JSAG
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+xOverhead joins are straightforward, but the CAA poster is misleading as it creates the impression that you can only join it from one direction. The reality is that it’s a big roundabout in the sky, with a diameter slighter longer than the runway in use. You join it from any direction, always turning in the circuit direction, and keep going round until abeam the landing threshold when you start your dead side descent to be at circuit height as you go crosswind. SkyDemon doesn’t depict all of that so it just gives you the final crosswind descent in the correct direction to a nominal circuit. It would be better if the nominal circuit bit was removed as it serves to confuse. I agree grahamb. The other piece of advice I was given was if it's a left hand circuit always have the airfield on your left as you approach, join the overhead and circuit. And visa versa.
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Chris_S
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The roundabout concept makes sense, so its in the same direction as the circuit at 2000ft, everyone enters at whatever position suits them but drops out of it when they reach dead-side. Presumably if you happen to arrive on the dead-side you can just descend as you go through the deadside and slot in like when you join the circuit. What if you don't know the circuit direction, perhaps if its unmanned or you need to see the big square runway direction sign?
Its the first I have heard of tis method despite the nav training and reading all the PPL books, I wonder how many people do this and how many people do something entirely different.
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Tony N
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+xThe roundabout concept makes sense, so its in the same direction as the circuit at 2000ft, everyone enters at whatever position suits them but drops out of it when they reach dead-side. Presumably if you happen to arrive on the dead-side you can just descend as you go through the deadside and slot in like when you join the circuit. What if you don't know the circuit direction, perhaps if its unmanned or you need to see the big square runway direction sign?
Its the first I have heard of tis method despite the nav training and reading all the PPL books, I wonder how many people do this and how many people do something entirely different. Chris, Remember that it should be 2000 ft above airfield height. So at somewhere like Compton Abbas you are overhead at something like 2850 ft AMSL! If you arrive at an unmanned airfield, you would already be self-briefed as to the "preferred" circuit direction! Just keep at the joining altitude until you have figured out wind direction and runway in use. I sometimes use Windy to get an indication of the surface wind at my destination, should the radio be unmanned or non-existent. Tony
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russellp
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I’ve always thought that the overhead join arrow should be a full U shape extending back as far as the downwind numbers for full clarity, however knowing this negates the need for it to be displayed that way, you simply have to know that it needs extending. If approaching from the dead side the correct point to join the roundabout in the sky is over the upwind numbers at ohj height and then circle to the downwind numbers without losing height before commencing dead side descent over the downwind numbers. No-one should need more than the runway length for a dead side descent. I guess extending to a full U would require SD to make a stand on the often controversial point about whether the dead side descent should start over the numbers (as most of us were taught) or nearly a mile away as depicted in the CAA diagrams above!
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JSAG
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David, that's a good point about confusion in overhead joins. The best advice from my instructor was if the circuit is rt handed always have the rwy on your right.
So as you approach the airfield, from whatever direction, have it to the rt of your nose, as you approach the overhead join have the rwy on your right and keep it on your right for deadside descent and obviously crosswind, downwind and base. Similarly if the circuit is left hand all the above but to the left hand side.
Once you've established the orientation of the circuit, left or right, and your initial approach is left or right the rest just flows.
It even helps the difficult approach from the deadside or even the final side. Say you are approaching from the deadside or final side of a left hand circuit, if you always keep the rwy to your left at 1300' above curcuit ht, flying round the field to the point where you descend and turn left into the SD purple arrow at 1000' above circuit ht you cannot conflict with anyone ahead of you.
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André
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Hi! I am a PPL-A student in Norway and the essence of this very topic has been difficult for me to grasp as there seems to be different opinions on how to do this procedure. My post is oriented more towards how to do a correct standard overhead join (SOJ), rather than how SkyDemon depicts it in the app. After all, if there are different ways of flying the SOJ, obviously SkyDemon (SD) can’t know how you are executing the SOJ procedure.
Reading through the post I must say my interpretation on how to execute the standard overhead join (SOJ) aligns with the understanding of ChrisB. Tim Dawson writes that it is not common to execute the SOJ from the live side if arriving from the dead/non-traffic side, but isn’t this a pilot error? Shouldn’t the SOJ always be flown as per definition? I don’t see the point of doing a SOJ if it is not as per definition, changing it up arguably attenuates the very point of a standardization, enhancing aviation safety through reproducibility and predictability. The post from David Jonstone is an example.
However, I definitely see that it is easier to just descend to pattern altitude immediately if arriving on the dead side, but now it is my understanding that you are not doing a standard overhead join, rather a modified overhead join. Please correct me if I am wrong!
So if you don’t mind a question from a PPL-a student with no practical experience on how to perform a SOJ, are we disagreeing on how to perform this procedure? Or do we agree on how it is done, but do not adhere to the SOJ procedure as per definition when actually executing it?
I just found this link explaining the SOJ procedure. Note the two diagrams. Do we agree that this is the correct way of doing it, every time?
So I guess there are several questions: Q1: are there different published standards on how to do this, eg. from EASA/Europe? Q2: how do you execute this procedure if different from the published standard? Q3: if there is one defined way of performing the SOJ, would it be better if SD changed the pink arrow to indicate arrival from the live side, 180 dgr turn with descent at the dead side before joining the pattern?
Please enlighten me and help me do this correctly =) Thank you very much!
Sources:
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