NVFR Departure - LSALT

[SB4200]

Gday

I was recently reading a book on the NVFR rating which described when it is acceptable to be below your LSALT.

For the departure scenario it described it as being ok so long as you can ensure "adequate terrain clearance" (or something along those lines) during the climb. GEN 3.3 para 3.11a says you can be below LSALT "during take-off and climb in the vicinity of the departure aerodrome".

Question: is this the only reference to this scenario in the air law docs? I can't find any other mention of it. I would have thought there would be more provisos. eg: "acceptable so long as a careful study of the applicable topographic charts shows that terrain clearance can be assured...." or something regarding ensuring you are actually on the correct departure track...

And what is "vicinity"? CTAF/MBZ boundary, circling area, something else?

Thanks in advance

[swh]

SB4200,

I was taught to climb in the circuit over the runway, for terrain clearance, and for somewhere to put down if you have an engine failure.

[HEALY]

You have LSALT calculations made for between two points. I have always used the basis of using 3nm because it is when you can decend below LSALT on arrival to the AD.

The term 'vicinity' I would suggest is 3nm because is when you are obviously required to be below LSALT and you are using topographical information and any known circuit restrictions to conduct both the arrival and departure procedure.

Having adequate climb performance I would of thought is more applicable to Engine Out departure for twins and for singles which may require 'overhead departures' to meet LSALT calculations by 3nm.

I have no references in front of me.....My ideas could be wrong.

[Hugh Jarse]

Agree with SWH.

Commonsense is a good tool to have in the kit too, SB4200. Study your topo charts thoroughly when planning your navex, and don't leave anything to chance......

Have fun.

[turning inbound]

"don't leave anything to chance".....NVFR in a single?????

agree with healy that LSALT by 3nm is the sensible course of action

[Arm out the window]

Scale of topo map also important - I'd want to use a 1:100 000 or better for circling area calculations; WACs are next to useless for that kind of thing.

[HEALY]

A common way people are taught nav at night is the idea of not using the WAC because of diminished light and all that, but draw a mud map with key features you are going to see during the flight. This is all well and good but wont help diddly squat when your below LSALT with terrain either side.

If you are being taught this way ensure you have a 'blown up' diagram of the 3nm area around every point you will be below LSALT and put in key points and heights which could cause serious amounts of noise and ruin a perfectly good night flight.

[Super Cecil]

If you can feel the propnoise reflecting off the fence through the airframe at the fence off the end of the strip then go back a hundred litres for the next load.

[Uncommon Sense]

To throw a further spanner in the works.....

I would be interested to see what different people's interpretation of this is:

How would you plan to depart YBAF at night (VFR) for YKRY, planned A045.

Assume YBAF is an MBZ and YBBN is on RWY01.