Aus CAO 82.6 NVG, OEI & enroute climb to LSALT

[Envoy604]

This might be better in D&G zone, but can someone help with a question on en-route RW NVG OEI planning considerations for twin-engine en-route flight.

Under the IFR if I lose an engine I must plan for and demonstrate sufficient single engine performance to climb to safe altitude with a 1% climb gradient from that point. If above LSALT I can drift down to, but not descend below a safe altitude.

Under NVFR I must also be able to maintain LSALT in the event of an engine failure en-route. If below LSALT on departure I must be able to climb to LSALT.

CAO 82.6 permits me to fly en-route below LSALT with the use of NVG. During day VFR, if I lose an engine I won’t climb, I will find a safe recovery and land. With NVG I can see the ground etc and I won’t climb, but will find a safe recovery and land. However, do I need to plan for and have sufficient performance to climb above LSALT?

So, given that NVG operations are conducted under NVFR with exemptions to fly below LSALT, what considerations must I give to the OEI case. That is, should I plan to have the performance and be able to climb to en-route LSALT even though I can see the terrain. If so, what are the relevant CAO/CAR etc??

Thanks

[spinwing]

Mmmmm ....

Might this question best be asked of your 'friendly' area FOI with his answer nicely phased and on CASA letterhead paper so you can amend your operations manual as may be required .....


:hmm:

[helmet fire]

Unfortunately, NVG flight must comply to the NVFR IAW CAO 82.6. NVFR is a set of rules as opposed to VMC which is a weather description.

The OEI bit applies to NVFR, and NVG is to be conducted under NVFR, thus OEI requirements apply to NVG flight. Here is the CAO bit which (kind of) requires NVFR to be applied:
CAO 82.6, Part 1, Para 5.3:
A permitted NVG operation may only be conducted in a helicopter that is at least equipped and maintained for NVFR.
Note NVG operations are an adjunct to flight under the NVFR. However, it is intended that the flight crew in an I.F.R. category flight may derive an operational advantage from NVG use under the I.F.R. when conducting a landing (after descending from I.F.R. LSALT) or take-off (with the intent of climbing to the I.F.R. LSALT) in accordance with the requirements detailed in the AIP. All other NVG operations below LSALT must be under the NVFR.

It is that last sentence that counts.
You might also note that CAO 82.6 only permits NVG flight below LSALT "if operationally necessary" so taking that as permission to fly enroute below LSALT may be a stretch.