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Genghis the Engineer
24th Mar 2015, 14:16
I'm just curious really - I know what I do, but I was taught two different approaches for my PPL and later my CPL. On the other hand, talking with another CPL holder the other day he was taught what I did for my CPL for his PPL, and vice versa.

What are training and examination norms around the bazaars for the start point of a VFR route?

G

Whopity
24th Mar 2015, 19:15
For PPL training the norm is to teach an overhead departure because it means the student comences the route at the planned altitude over a known position. Of course at some locations this is not practical so an offset start point would be used as an alternative. A CPL candidate would be expected to be commercially expedient and turn out onto the first track.

Mach Jump
24th Mar 2015, 19:22
For PPL training, to give the Student a fixed point from which to navigate, I teach either overhead departures, or visual positioning to a landmark remote from the airfield, as appropriate for the location.

CPL Students however, should be able to cope with an initial turn to intercept a track drawn direct from the departure airfield, whilst starting the timing when abeam.


MJ:ok:

Ps. Always nice to know I'm not alone.

3 Point
25th Mar 2015, 11:29
I agree with Whopity and MJ; that's what I teach.

3 Point

Genghis the Engineer
25th Mar 2015, 16:27
Interesting.

I was taught to navigate from the airfield on my two PPLs (M then SEP), then for my CPL told to use start points. For my real world VFR nav, I in reality pick a start point not far from the airfield and as near as dammit on a straight line route to first proper waypoint from the airfield if precision nav is really important (microlight cross country competitions for example), but just start at the airfield if it's not.

What brought this to mind was flying for an SEP reval with a lapsed low-hour CPL holder who told me that he was taught to use a start point for his PPL, but to start from the airfield for his CPL.

Looks like the way I learned was in the minority, but the way I actually fly is a pragmatic halfway anyhow.

G

Whopity
26th Mar 2015, 08:28
When students have been taught to commence their Navex at a "start point" rather than overhead, its quite common to see they make no fuel or time allowance on the PLOG for the section between the airfield and the start point.

I recall one student, a fellow of Balliol college, who failed to find any of the turning points including a start point. He then left the keys in the ignition with the control lock over the top!

Genghis the Engineer
26th Mar 2015, 11:48
That's just Oxbridge for you !

G

lasseb
26th Mar 2015, 14:52
Here in the southern Scandinavia, we teach turn and intercept immediately after departure, when at safe altitude. This goes for all levels (LAPL,PPL,CPL). It's not really complicated. If you cannot do this when flying PPL, how would you ever get back on track while enroute?
Maybe it's a UK thing to do this overhead thing?
Just a waste of time and fuel IMHO.

Level Attitude
26th Mar 2015, 15:17
When students have been taught to commence their Navex at a "start point" rather than overhead, its quite common to see they make no fuel or time allowance on the PLOG for the section between the airfield and the start pointWhichever method they use to calculate fuel required, all pilots (including students) should take in to account the whole duration of the flight - and that includes the fuel burn for a climb from Take Off to the Overhead.

foxmoth
26th Mar 2015, 20:46
I used to start from OH for PPL students but then decided it was not a practical way of doing things for once people have got their licence so why teach that in the first place? By the time they get to Nav most students will be used to flying in the local area and back so I now teach flying to a landmark en route and just outside the ATZ and starting from there. For fuel In most light training aircraft I normally suggest allowing a gallon to this point, this will normally be enough to get to a point 3 miles away including enough for the climb and means you can then calculate the rest of the flight at a cruise fuel flow.

Pull what
6th Apr 2015, 21:54
Why encourage a student to climb to the overhead of an airfield that may be busy with other traffic or even have transiting traffic when a much safer option is to select a start point (exit point) away from the airfield that he can fly to and then start the cross country(and nav log) from that point. Its also a waste of fuel and money to go to the overhead.

This is yet another relic from the Tiger Moth days of instructing.

Same as with always teaching to join overhead, it may be the safest student option at an unfamiliar airfield that is busy but that doesnt mean it should be taught as the only way to join an airfield. Noticeably some PPLs also seem to think that they always have to join a GA airfield from the overhead.

Teaching expeditious arrivals and departures should be part of the syllabus

funkydreadlocks
19th Apr 2015, 22:59
This is an interesting thread for me, someone who did his PPL in France.

You see, us cheese loving monkeys love to stick to the traffic pattern in VFR. Almost every airfields have an official or unofficial arrival/departure points that join the traffic pattern and pretty much all VFR AC have to go to these points before they're allowed to start their nav.

In terms of fuel calculations we always approximated 30min of cruise fuel for T/O, climb to what we called "departure altitude" and reaching one such point. The same for arriving at an airfield, 30min. Only exception would be when there was a considerable distance between these points and integrating into the traffic pattern, in which case a more precise fuel calculation was done.

Never ever ever heard of calculating navs by starting overhead the departure airfield.

Reverserbucket
20th Apr 2015, 13:17
O/H Departures seem to be a very British thing in my experience - I've not seen them taught elsewhere. Agree with Pull what on the busy circuit and other traffic considerations for a 'Commercial' Departure but will add that not all aerodromes are suitable for proceeding from the overhead in any event: those that sit within regulated airspace and have special entry/exit arrangements or in close proximity to hazards such as PDZ's or Danger/Restricted Areas may be more suited to 'Remote Start' navex planning.


Departing from the overhead is however a pure and accurate form of navigating for an early PPL student and I like it as a teaching exercise, but for the reasons mentioned in terms of time/fuel, it's not particularly commercial.

hugh flung_dung
21st Apr 2015, 12:11
If an initial leg to a nearby prominent feature (preferably in the right direction) is planned then the first significant nav leg can start from a known point at somewhere near cruise level and speed without the problems of an O/H departure. Similarly, planning an arrival to a nearby prominent feature and then a short planned leg from there to the destination reduces those "where's the airfield gone" moments. Simples:ok:
Clearly, fuel for all legs needs to be part of the plan.

Thread creep: for track correction I prefer either double track error or standard closing angle, what do others teach?

HFD

TheOddOne
21st Apr 2015, 18:53
The issue with standard closing angle where the track passes close to controlled airspace is that it may lead to an infringement; double track error is potentially much quicker at getting back on track (unless you do what one student proposed to me, do a 90 deg turn towards the track!!)

However, standard closing angle minimises time loss and extra fuel burn, though on the small errors we ought to be correcting for, it probably doesn't make much difference.

TOO

hugh flung_dung
21st Apr 2015, 21:16
Au contraire mon brave, the STANDARD closing angle (SCA) method gets back to track faster than doubling the track error angle - did you misread it as just Closing Angle?
I find that people prefer SCA because they can estimate the cross track error distance more easily than the track error angle, and it can also be used most of the way to the destination whereas double track error gives-up at the half way point.

HFD

dobbin1
21st Apr 2015, 22:24
Standard Closing Angle every time for me. Works beautifully and involves no hard sums. And it gets you back on your original track ASAP.

TheOddOne
22nd Apr 2015, 17:04
did you misread it as just Closing Angle

Mea culpa.

RTFQ

TOO