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Guest Divergent Phugoid

Traffic patterns and erm, stuff

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Usually I just follow the instructions given to me by ATC in FS2002 for landing at an airport.But, what about these traffic patterns, base leg, crosswinds etc i keep hearing about? Can someone explain? I like landing at heathrow, so if you want to throw degrees at me, base it on that (I can take off land and everything at egll blind folded).Thanks

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This is a traffic pattern:http://stoenworks.com/images/How%20to%20fl...c%20pattern.jpgLets say you are approaching Heathrow in a little Cessna from the south and you want to land on runway 27L.http://www.stvincent.ac.uk/Resources/Physi...es/heathrow.gifYour heading would be 360. As you get closer you will turn right on a heading of 045 to set up for the entry into the pattern.To get into the traffic pattern you would get close to the airport and then turn right 090. You are now on the downwind leg - parallel to runway 27L.Once past the end of the runway you would turn left heading 360. This is your base leg.As you approach the extended centerline you will finally turn onto heading 270 to land on 27L. This is the finals leg.Hope that helps a bit!

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For VFR flights in the UK the Standard Overhead Join is shown as:- Cross the upwind threshold (landing end) of the runway at 1000ft above circuit height.- Descend to circuit height on the dead side where the airport elevation is shown in the previous post (ie the side opposite to the down wind leg) while turning to fly parallel to the runway.- Turn onto the crosswind leg to cross the downwind threshold (takeoff end) of the runway at circuit height- Turn onto the downwind leg

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This is also (more or less, 500' above circuit is OK for entry) standard in New Zealand and Vietnam (because they photocopy the NZ regs, having outsourced all their aviation standards and regulations to NZ), but not in Australia or the US, where either a join base or a join early downwind at a 45 degree angle (i.e. 135 degrees heading for RWY36) and at circuit height is required. I don't know about other countries. Frankly, I consider the US and Australian practice unsafe, as you don't get a very good look at the field first, but it is necessary to follow local procedures.

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I don't see what's unsafe about the 45 degree midfield downwind entry at TPA. It affords you an excellent view of the field and traffic as you approach.----------------------------------------------------------------John MorganReal World: KGEG, UND Aerospace Spokane Satillite, Private ASEL 141.2 hrs, 314 landings, 46 inst. apprs.Virtual: MSFS 2004"There is a feeling about an airport that no other piece of ground can have. No matter what the name of the country on whose land it lies, an airport is a place you can see and touch that leads to a reality that can only be thought and felt." - The Bridge Across Forever: A Love Story by Richard Bach

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Maybe it's OK; not actually having done that (since it's against the local rules) I'm not really sure. However comparing some of the procedure arrivals at NZCH which end up being a join downwind on the 45, I can never really see the windsocks until I'm on finals, which means you have to have other information for selecting a runway (obviously, a procedure arrival means controlled airspace, which is fine). Overhead joining means you get to look at all the windsocks, and if the field is not just uncontrolled but completely inactive, you get to see the condition of the runways and if there are animals, vehicles, or other random stuff on the field.

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In the case of that where we can't get weather from an ASOS (the majority of the public local fields have ASOS in the Spokane area) We would do an overflight of the field at 500-1000 feet above the TPA then teardrop into the traffic pattern.----------------------------------------------------------------John MorganReal World: KGEG, UND Aerospace Spokane Satillite, Private ASEL 141.2 hrs, 314 landings, 46 inst. apprs.Virtual: MSFS 2004"There is a feeling about an airport that no other piece of ground can have. No matter what the name of the country on whose land it lies, an airport is a place you can see and touch that leads to a reality that can only be thought and felt." - The Bridge Across Forever: A Love Story by Richard Bach

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>Maybe it's OK; not actually having done that (since it's>against the local rules) I'm not really sure. However>comparing some of the procedure arrivals at NZCH which end up>being a join downwind on the 45, I can never really see the>windsocks until I'm on finals, which means you have to have>other information for selecting a runway (obviously, a>procedure arrival means controlled airspace, which is fine). >Overhead joining means you get to look at all the windsocks,>and if the field is not just uncontrolled but completely>inactive, you get to see the condition of the runways and if>there are animals, vehicles, or other random stuff on the>field.Andrew The overhead join has to be the most dangerous, outdated procedure available.Not only does it require aircraft all heading from different directions to a point above the airfield but it then involves those aircraft making up to five ninety degree turns and often blind turns.This is a mixture of high and low wing aircraft.Coming into an airfield downwind at circuit height I was nearly taken out by a student who was trying to make an overhead join under a low cloudbase at 1200 ft agl and cutting right across the down wind leg.He was riding just below the cloudbase when he was supposed to be 500 feet vertically clear of cloud and 2000 feet above the airfield.The overhead join is a monstrocity from the past in non radio days when aircraft had very poor navigation aids and had to go overhead to examine the signal square and check that they were indeed over the correct aifield.Peter

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That was my concern with the overhead idea. In all planes you can't see below you straight ahead and in a low wing you add the inability to see just about anything below you.----------------------------------------------------------------John MorganReal World: KGEG, UND Aerospace Spokane Satillite, Private ASEL 141.2 hrs, 314 landings, 46 inst. apprs.Virtual: MSFS 2004"There is a feeling about an airport that no other piece of ground can have. No matter what the name of the country on whose land it lies, an airport is a place you can see and touch that leads to a reality that can only be thought and felt." - The Bridge Across Forever: A Love Story by Richard Bach

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Interesting. Well, it's standard procedure here, and the stated reason is to give an opportunity to look at the field. We don't get that much traffic here, and when we do have busy uncontrolled airfields they have published procedures, which generally specify some other join. We do have a lot of airfields that get very little traffic, you might be the only landing all day, which makes it very important to get that look.I do take your point about lots of traffic arriving at a point, that can be dodgy.

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>>The overhead join has to be the most dangerous, outdated procedure >>available.>>Not only does it require aircraft all heading from different directions >>to a point above the airfield but it then involves those aircraft >>making up to five ninety degree turns and often blind turns.I so complete disagree. All aircraft join in the same direction regardless of where they arrive from. If you are landing 09 and you arrive from the south then join at 2000' over the "09" numbers and start your descent deadside (the side of the runway away from the circuit). There is no risk of interfering with other traffic. If you join from the north then you overfly the "27" numbers at circuit height at 2000' over the "27" and circle until over the "09" numbers before descending. The only point of confluense two converging aircraft would be at the same height in a level attitude, the best conditions for visual contact. If it is a left hand circuit then all turns are to the left. It is very simple, efficient and safe with no risk of descending on top of anybody else and promotes excellent situational awareness.Base joins require the mose care, downwind joins rely on the joiner doing the seeing as crosswind aircraft will probably still be in the climb and turning. Joining crosswind also affords very good visibility an situational awareness, although at longer runways it is best to do an intermediate crosswind join (halfway along the runway) as light aircraft could be near circuit height at the upwind numbers.

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The name of the standard joining procedure is the "overhead Join".The reason for this join goes back to the days when aircraft were often non radio, had no or very little navaids.The idea was to be in a position where you could see the signal square and firstly check which runway was in use.The overhead join does not require you to be over the numbers of the active runway.people will join overhead regardless of the cloudbase so typically if the cloudbase is 2000 feet they will scud run to the overhead.If the cloudbase is 1500 feet they still scud run to the overhead.Surprise :-) if the cloudbase is near circuit height they still attempt to join overhead cutting through circuit patterns.Aircraft join overhead from all different directions descend deadside and as stated this requires more 90 degree turns than a straight in base or downwind join.Mixing high and low wing aircraft is fraught with danger and creating a situation where more 90 degree turns are needed has to increase the collision potential.While the overhead join has its uses in my opinion with aircraft which have GPS and excellent radios it should be just one joining procedure if conditions are correct.Overhead joins should be banned where an aircraft cannot join overhead at 2000 feet and still remain 500 feet clear of cloud ie the cloudbase has to be a minimum of 2500 feet above airport height. These minimal legal requirements are rarely met.Peter

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>>The name of the standard joining procedure is the "overhead Join".>>The reason for this join goes back to the days when aircraft were >>often non radio, had no or very little navaids.An overhead join is specifically when you join at 1000' above circuit height over the downwind numbers. Joining deadside is a crosswind join. Other airfields have all sorts of different ways of joining over the top of the airfield but they ain't overhead joins. The use of the term ovhead join means only one thing...as it should. Also, it has nothing to do with navaids, it is a VFR manoeuvre and is relevant regardless of the type of aeronautical ground station in operation. Also, I think saying mixing high and low wings is fraught with danger is pretty much a wild exageration.>>Surprise :-) if the cloudbase is near circuit height they still >>attempt to join overhead cutting through circuit patternsWhere? Not at any airfield I have visited. Here in the UK we do things properly ;o)>>While the overhead join has its uses in my opinion with aircraft which have GPS and excellent radios it should be just one joining >>procedure if conditions are correct.You what? GPS? What on Earth has GPS got to do with a join? What qualifies a radio as being excellent as opposed to just be servicable.Also, if you do your pre-flight planning properly then you will know that all airfields either have a bad weather circuit procedure or a minimum cloud base for accepting arrivals.

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>>Surprise if the cloudbase is near circuit height they still >>attempt to join overhead cutting through circuit patternsWhere? Not at any airfield I have visited. Here in the UK we do things properly ;o)>>While the overhead join has its uses in my opinion with aircraft which have GPS and excellent radios it should be just one joining >>procedure if conditions are correct.You what? GPS? What on Earth has GPS got to do with a join? What qualifies a radio as being excellent as opposed to just be servicable.In my time I have probably visited every airfield in the UK and I can assure you that we do not do things properly ;-)With GPS you have the ability to give a DME range which is more accurate than an estimation.Hence XYZ is 6 mile final R/W 23 or XYZ is 3 Mile Final R/W 23GPS also allows you to go to OBS mode and place in the runway centreline as well as a host of other useful location helps in the pattern.I think you need to check what a standard overhead join is? ;-)Peter

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Try this:www.caa.co.uk/default.aspx?categoryid=64& pagetype=90&pageid=2244

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Either you are on a wind up mission, your examiner thought it was a good time for nap or things aren't what they appear. Suggest you read up on DME, grab a copy of CAP 413 and the ANO.

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>Either you are on a wind up mission, your examiner thought it>was a good time for nap or things aren't what they appear.>Suggest you read up on DME, grab a copy of CAP 413 and the>ANO.I'd agree on advantages of GPS over DME for coming up with quick distance measurements.But other than that, I know that Peter has been flying Cessna Citation jet's and a Piper Seneca all over Europe for at least ten years; therefor I'd have to imagine that he is aware of just what DME does and doesn't do. Especially since he has posted all those excellent in the cloud IMC pics over the years.L.Adamson

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That looks a lot like a field overflight in the US when you attempt to find the wind indicator on field. Though we ussually fly more midfield of the runway. If we're flying over into what you guys call the live-side, we'd simply go out further than the traffic pattern should be and start a descending tear-drop to make our 45

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JohnPractically and in reality as well as historically most overhead joins are midfield or to the point where the NDB or GPS referance point is located.Historically it was to a point where you could see the signal square and find out which runway was in use in non radio aircraft or airfields with no tower facilities.Even in the CAAs literature they are contradictory firstly staing that you should join overhead the landing runway end then stating that if you dont know which runway or become confused you should circle overhead ;-)Any procedure which involves aircraft making needless 90 degree turns has to be hazardous especially where low and high wing aircraft are mixed together.To complicate matters even further many airfields use two circuit heights. One for slow singles another for faster twins and jets.practically airfields do not like faster twins or jets involved in overhead joins and usually give a left base, downwind or straight in approach but there again I dont suppose Divergent Phugoid has flown anything faster than a 150.Peter

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The allowable type of join is often more complicated and in the UK is may be specified in the AIP - often in "2.20 Local Traffic Regulations" or "2.22 Flight Procedures". Many aerodromes are not available to aircraft unable to communication by radio,Not all aerodromes have specific joining instructions but examples of joining are:Duxford (EGSU) where there are no overhead joins to assist "in deconfliction of circuit patterns"Bembridge (EGHJ) where when gliders are operating "joining aircraft are to overfly the aerodrome at 1500 QNH and the runway QDM. When over the upwind end of the runway turn left or right (depending on the circuit direction) to level at crcuit height 1000 ft QFE on crosswind leg prior to turning downwind"Redhill (EGKR) "If required to join overhead enter the ATZ on the runway QDM remaining within the fixed-wing circuit area. When instructed descend to circuit height and join the visual circuit pattern"Shoreham (EGKK) "Unless otherwise instructed aircraft joining the circuit will overfly the areodrome maintaining 2000 ft aal, until instructed to descend to circuit height on the inactive (dead) side of the runway in use and joun the circuit by crossing the upwind end....Aircraft joining direct to the crosswind leg should arrange their flight track over the upwind end of the runway-in-use, ie in the same position as if approaching it from the '"deadside'

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Yes indeed. I already alluded to this with my earlier comment "Joining crosswind also affords very good visibility an situational awareness, although at longer runways it is best to do an intermediate crosswind join (halfway along the runway) as light aircraft could be near circuit height at the upwind numbers."Most runways aren't really long enough so the "intermediate crosswind join" is less well known. Larger fields are often ATC and so you would be vectored onto a right or left base. But there are some large AFIS or A/G fields where you are not under control of anything other than the airfields published joining procedures (if any). It is often unadvisable to join base or straight in with other aircraft in the circuit and unless you are visual with crosswind or t/o traffic a downwind join can result in a few hasty manouevres. This is where the overhead join allows to you take a good look around before you descend and I complete agree with the CAA, if you are disoriented circle until you have your bearings.The mixing of high and low wing is only really a problem if a/c are descending at different points in a busy circuit, with the overhead join everyone starts the descent at the same point so the risk to comparatiely negligable.In the UK we have a dedicated radio frequency for unmanned fields (not quite the same as UNICOM) so traffic can communicate position and intention at the key reporting points in the circuit. Again, an overhead join in this case is useful if you can hear the other aircraft(s) but can't see it(all of them).

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UNICOM is semi-dedicated, it ussually covers several fields in the area unless the field is a notoriously congested uncontrolled field then it will have it's own readio frequency. Standard phrasiology for uncontrolled fields in the US is field name, your plane and tail number, approxamate distance and direction, altitude, intentions, then the field name. I.e. "Deer Park Traffic, Cherokee One-One-Three-November-Delta three miles south west of the field at four thousand five hundred, inbound to overfly the field, Deer Park Traffic." The field is said twice incase someone comes on the frequency part way into your communication or spaced the field name and is wondering, "Did he just say Deer Park?"If you are disoriented into a US field, you probably didn't look at the airport in the Airport/Facility Directory. I've ussually got a diagram drawn out on my kneeboard if the A/FD has it drawn or atleast bassic information such as TPA, runways dimentions and directions and traffic patter directions for the runways, as well as airport elevation.In the US you are not required to land into the wind at an uncontrolled airfield, what you do is your choice, but you do not want to interfere with traffic in the area. Voice communications are not required but recommended, all aspects that ag-pilots in our area seem notorious for (I know, I know, it's not most of them, but I've been put in dangerous situations by atleast 3 that shot a straight in final under me while I was on final).At uncontrolled fields; where you can easily see the sock (I have yet to see a tetrahedron or anyother windmarker in my area), get weather information from an ASOS/AWOS, or see current traffic direction in the pattern; you would just enter the pattern on a 45 for the downwind (a crosswind join was never even mentioned in groundschool) at TPA to stay out of anyones blindspot and if you're a low-wing to keep the traffic pattern out of yours.----------------------------------------------------------------John MorganReal World: KGEG, UND Aerospace Spokane Satillite, Private ASEL 141.2 hrs, 314 landings, 46 inst. apprs.Virtual: MSFS 2004"There is a feeling about an airport that no other piece of ground can have. No matter what the name of the country on whose land it lies, an airport is a place you can see and touch that leads to a reality that can only be thought and felt." - The Bridge Across Forever: A Love Story by Richard Bach

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>>If you are disoriented into a US field, you probably didn't look at the >>airport in the Airport/Facility Directory. I've ussually got a diagram >>drawn out on my kneeboard if the A/FD has it drawn or atleast bassic >>information such as TPA, runways dimentions and directions and traffic >>patter directions for the runways, as well as airport elevation.Basic text book stuff. We can't choose our mistakes, we can only make them less likely to happen and your planning methodology is a step in the right direction, but that is all. Not being mentally prepared for screw ups only serves to compound problems when they do occur. If you are mentally geared up to abort a manouevre, then IMHO the chance of you attempting to see it through to the bitter end is reduced by several orders of magnitude. Saying that you only get disoriented because you didn't have the plate on your kneepad fails to account for the veritible myriad of other things things, that added together, can make a 'simple' approach at best embarrasing and at worst...well you know.

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I guess I take for granted my natural ability to take a map and convert it into a 3D image in my head. So far, I haven't found a field that has disoriented me, my diagrams on my kneeboard include all known information of the field: location of windsocks, obsticles in the vincinity, and roads near it, etc. My training has taught me to run by the rule of three: Have atleast 3 distiguishable features to identify something. IFR in approaches, I've gotten disoriented on NDB approaches quite a bit lately. I'm also blessed with flying in a region with a lot of uniquely identifiable geological features. The only few times I've come to an airport disoriented was because I failed to do my research of the field before hand and was at the last second digging in my flight bag to grab my AF/D. Boy was that embaressing. :-lol----------------------------------------------------------------John MorganReal World: KGEG, UND Aerospace Spokane Satillite, Private ASEL 141.2 hrs, 314 landings, 46 inst. apprs.Virtual: MSFS 2004"There is a feeling about an airport that no other piece of ground can have. No matter what the name of the country on whose land it lies, an airport is a place you can see and touch that leads to a reality that can only be thought and felt." - The Bridge Across Forever: A Love Story by Richard Bach

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