G’day,

I recently purchased a new IREX book to get familiar with the changes and location of the new rules.

On page 155, the example question states you have 2 TSO 145s, however the explanation below it is specifying the aircraft is equipped with TSO 129s.

Would the correct answer be no alternate is required due to aids, however one is needed for the cloud being below the alternate?

Also, on page 130 for the TAF3, it specifies that any arrival after 1100 doesn’t need the buffers. Is that time correct? To me that TAF has a validity between 00 and 06UTC. Was that 1100 confused with the date of 08?

G'day

Page 155 is a typo I will amend that it was meant to reflect the two 145 GNNS on board

as for page 130 we will note that the paragraph says


As an arrival after 1100 does require the 30 minute buffers.

Cheers

The way I see that taf is it is valid from the 8th at 0000UTC to the 9th the next day till 0600UTC.

So wouldn’t that mean that the 30 minute buffers apply from 0300UTC and not 1100UTC?

Thanks for the help so far.

Hi Stuart.

Regarding page 155. The book and online version list 2x (E)TSO 129 GNSS, but the last paragraph next to the chart plate on page 155 says.

"Note that the GNSS equipment you
have would satisfy the alternate re
quirement for navigation aids and
if the weather had been above the
alternate minimum, you would not
have needed an alternate."

I thought the 2x TSO C129's wouldn't satisfy the alternate requirement, because MOS 135 11.09 (7) says TSO C129's are not allowed and MOS 135 11.09 (8) says TSO C129 is not allowed unless the A/C was manufactured before 6 Feb 2014 and the GNSS installed before 6 Feb 2014.

Cheer
Matthew

If you reread that paragraph, you'll note it will "satisfy the alternate requirement for navigation aids
if the weather had been above the alternate minimum"

But you don't need to bother with an alternate.

Also look at the bottom of page 154 and you will notice that it acknowledges that "the flight to the alternate must be navigated using a ground-based aid or DR"

Thanks Stuart. Got it. I think.

I've tried to compile the requirements, to help me. Are these right?

IFR Alternates - Aids.
MOS 91 8.08 -
Day - No Alternate required if Airfield has no TAF, therefore no IAP's and GAF forecasts cloud above LSALT + 500 for final route segment and Visibility greater than or equal to 8Km.
Day - No Alternate required if airfield has IAP's and TAF forecasts cloud above IAP minima and Visibility greater than IAP minima.

Night - Alternate required if Airfield has no IAP, or IAP's that pilot cannot use.

MOS 91 8.05
Alternate - night only - must be within 1 hr flight time unless original destination has ground based aid, aircraft and pilot can use that aid, or Aircraft has GNSS and pilot can use it.

If GNSS is only (E) TSO C-129. Navigation to Alternate must be planned using non GNSS system.

IFR Instrument requirements.
Prvt - Part 91 26.08 (assuming Air Transport too, even though Air Transport comes under Part 135)
All IFR flights (Prvt - Night and Day. Air Transport - Day only) must be fitted with at least 1 GNSS.
GNSS must be greater than (E) TSO C-129, if A/C manufactured on or after Feb 6 2014.
GNSS must be greater than (E) TSO C-129, if A/C manufactured before Feb 6 2014 and GNSS installed on or after Feb 6 2014. (Which I assume means that if A/C was manufactured before Feb 6 2014 and GNSS installed before Feb 6 2014, then GNSS can be (E) TSO - C129.)

Air Transport Instruments - Night - Part 135 11.09
For IFR flights at night. A/C must have 2 x GNSS, or 1 x GNSS and either a VOR, or ADF.

That looks Ok to me