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Cecco
30th May 2011, 13:51
Hello,

Lostcomm procedure: maintain routing, speed and level for 7 minutes, then
direct to the next waypoint and according to the current fpl to destination,
iaf, commence normal instrument approach, as close to EAT, or expected approach time.

Now, what if you lost comm at FL100 and filed flight level was 380. Supposing, all other means to establish contact both comms, satphone etc.
fail and you are in IMC. And letīs suppose the MORAs ahead are ABOVE FL100and/or fuel would not be sufficient at that Flight Level. What then? You cannot climb/descend on your own accord with lostcomm, can you? Except when reaching the IAF, you are supposed to descend in the holding there, right (unless specific lost comm procedure at airport is overruling that). How would you proceed with that altitude problem?

Cheers
Cecco

Spitoon
30th May 2011, 16:10
As I recall, when the harmonised European RT fail procedures were introduced this issue was not addressed - I don't know whether the common European procedure has been amended since it was first published.

In the UK I seem to remember that the European procedure was amended to address two or three fairly major weaknesses in the Eurocontrol-prepared procedure. Certainly the procedure currently published in the UK AIP starts with:

A flight experiencing communication failure in IMC shall:
(a) Operate secondary radar transponder on Mode A, Code 7600 with Mode C.
(b) (i) Maintain, for a period of 7 minutes, the current speed and last assigned level or minimum safe altitude, if this higher.
....
ENR 1.1.3 para 4.2.4.1

poldek77
30th May 2011, 17:27
These apply also outside the UK. That's what we can find in Jeppesen RM, Emergency E-23 (the page is dated 02 JAN 2009):

RADIO COMMUNICATION FAILURE PROCEDURES EUROPE

Ref Regional Supplementary Procedures, DOC 7030/4 -EUR, Part 1, Rules of the Air, Air Traffic Services and Search and Rescue,
ACTION IN THE EVENT OF AIR GROUND COMMUNICATION FAILURE
....
INSTRUMENT METEOROLOGICAL CONDITIONS
A controlled flight experiencing communication failure in IMC, or where it does not appear feasible to continue in VMC shall:
1. set transponder to code 7600;
2. maintain fora period of 7 minutes the last assigned speed and level or the minimum flight altitude, if the minimum flight altitude is higher than the assigned level. The period of 7 minutes commences:
....
3. thereafter, adjust level and speed in accordance with the filed flight plan;
....

bookworm
30th May 2011, 18:39
maintain routing, speed and level for 7 minutes, then direct to the next waypoint and according to the current fpl to destination,

(Assuming radar) No, maintain speed and level for 7 minutes -- the routing should be according to flight plan from the outset. If being radar vectored, proceed directly to rejoin the flight planned route no later than the next significant point. In the UK (only), you keep the vector for 3 mins.

And letīs suppose the MORAs ahead are ABOVE FL100and/or fuel would not be sufficient at that Flight Level. What then?

After the 7 mins, you climb in accordance with the flight plan. If the minimum altitudes are lower than your current level, you climb to the minimum altitude even before the end of the 7 mins.

You cannot climb/descend on your own accord with lostcomm, can you? Except when reaching the IAF, you are supposed to descend in the holding there, right (unless specific lost comm procedure at airport is overruling that).

According to the ICAO procedure, yes, you maintain cruising latitude to the IAF. In the UK only, you arrange the flight to arrive over the IAF at the highest notified Minimum Sector Altitude taking account of en-route terrain clearance requirements. That's a significant difference.

Cecco
1st Jun 2011, 09:40
Your posts clearly answer my questions.

However, I have trouble imagining a lost comm-aircraft descending at the IAF in the holding from e.g FL380 to 4000ft. Do you know of any incidents where an aircraft had an early radio failure and then continued to the destination with climbing/descending according flightplan included?

Cheers
Cecco

Jagohu
6th Jun 2011, 11:35
INSTRUMENT METEOROLOGICAL CONDITIONS
A controlled flight experiencing communication failure in IMC, or where it does not appear feasible to continue in VMC shall:
1. set transponder to code 7600;
2. maintain fora period of 7 minutes the last assigned speed and level or the minimum flight altitude, if the minimum flight altitude is higher than the assigned level. The period of 7 minutes commences:
....
3. thereafter, adjust level and speed in accordance with the filed flight plan;
....

n+1. stand by for interception :)