IFR: Missed approach tracking requirements
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Nice one... Capt Arr.. that is a nice succinct way of explaining it. What happens though if the reason you have discontinued the approach is because you go out of tolerance on the LLZ? You obviously can't then use the localiser to track to the MAP....
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MAP ILS/LLZ when LZZ fails or you're out of tolerance
If the localiser fails while on the approach, you must to DR your track to the Missed Approach Point, while climbing to the MAP ALT. Not really nice if it happens inside to OM, especially where there are hills right next to the runway.
Also other traffic might separating itself (or ATC in CTA) with your expected track via the procedure including the missed approach. Could get ugly if the procedure is not flown as published.
I have however seen some jets below LSALT well into the ILS approach require a MA due weather and turn immediately out to sea. If there is no other traffic is the safety of the aircraft at risk?......or the the Capt ensuring the safety of the aircraft by avoiding the hazardous weather. The later I would suppose.
Also other traffic might separating itself (or ATC in CTA) with your expected track via the procedure including the missed approach. Could get ugly if the procedure is not flown as published.
I have however seen some jets below LSALT well into the ILS approach require a MA due weather and turn immediately out to sea. If there is no other traffic is the safety of the aircraft at risk?......or the the Capt ensuring the safety of the aircraft by avoiding the hazardous weather. The later I would suppose.
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back to the original question...
one requirement for a missed approach is if the navaid is suspect/fails.
where would the logic be in basing a missed approach on a procedure which requries the nav aid for tracking?!
DP
one requirement for a missed approach is if the navaid is suspect/fails.
where would the logic be in basing a missed approach on a procedure which requries the nav aid for tracking?!
DP
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Interesting point DP, I looked into the AIP's and couldn’t find an answer to your qn.. Let me know if you find an answer. My guess would be to make an initial climbing turn to the landing runway and circle overhead the aerodrome until you are above the MSA. I think it all really depends on the position of the aircraft at the time the aircraft's radio aid became suspect or failed. If you’re lucky enough to have a secondary ADF/VOR on board then use whatever navaid is working. I wouldn’t go flying in IMC with only one navaid on the ground or aircraft anyways. At least 2 ADF's or VOR's. what would happen If you arrived to the airport still in IMC, running low on fuel, with only one navaid and it fails? then you really have a problem!! ...
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If the aid became suspect/failed during the approach you would DR track to the MAPt then fly the MAP from there.
I think you're getting mixed up with losing visual reference while circling? where you would make the climbing turn towards the runway....
My point from my previous post, was looking more at why the MAP is a DR track... not a nav aid track.
I think you're getting mixed up with losing visual reference while circling? where you would make the climbing turn towards the runway....
My point from my previous post, was looking more at why the MAP is a DR track... not a nav aid track.
I have never seen this as particularly complex.
There is clearly a "protected" area associated with the Approach when flown correctly. If you are unsure of any aspect of the approach at any time, put the aircraft in a max angle climb and follow the approach procedure (in plan but not profile) using your best DR until you reach either the MAP or the DP - and then follow the MA as published until back at the appropriate LSA.
Chances are you will not hit anything!
Dr
There is clearly a "protected" area associated with the Approach when flown correctly. If you are unsure of any aspect of the approach at any time, put the aircraft in a max angle climb and follow the approach procedure (in plan but not profile) using your best DR until you reach either the MAP or the DP - and then follow the MA as published until back at the appropriate LSA.
Chances are you will not hit anything!
Dr
".... but how would you track to a MAPt if the ADF/VOR failed in IMC ...."
If it were me I would:
If outbound in the Appr - commence a climb back to the LSA while trying to stay within the safe area of the appr. ie continue to track outbound for the indicated time, turn in the same direction as indicated on the appr chart, track back towards the aid by best bet DR and continue to time inbound, if not at LSA when back roughly over the aid then carry out the MAP using DR to make good a track.
If anywhere else in the appr - same thing. Start a climb - follow the appr plan profile and MAP to the LSA.
This is all kinda academic really. Unlikely that anyone these days is going to be flying an appr in imc with just an ADF or VOR. Start a max angle climb and use your GPS to return to the aid and the LSA then go fly the RNAV Appr, which I would have been flying in the first place.
Dr
If it were me I would:
If outbound in the Appr - commence a climb back to the LSA while trying to stay within the safe area of the appr. ie continue to track outbound for the indicated time, turn in the same direction as indicated on the appr chart, track back towards the aid by best bet DR and continue to time inbound, if not at LSA when back roughly over the aid then carry out the MAP using DR to make good a track.
If anywhere else in the appr - same thing. Start a climb - follow the appr plan profile and MAP to the LSA.
This is all kinda academic really. Unlikely that anyone these days is going to be flying an appr in imc with just an ADF or VOR. Start a max angle climb and use your GPS to return to the aid and the LSA then go fly the RNAV Appr, which I would have been flying in the first place.
Dr
Good point Doc, so then if ye lose the LLZ as well, I be thinkin there are nay airports with ILS which be lacking in the VOR/NDB area, so then if ye lose the LLZ, the obvious course of action be to tune in the VOR or the NDB and be setting a course for that aid instead, on climb to the LSA.
If the NDB be yer only approach, I be thinkin of a safe track out away from yonder hills when the ****e be hitting the proverbial before I be departing the hold. Assuming an escape exists.
Arrr!
If the NDB be yer only approach, I be thinkin of a safe track out away from yonder hills when the ****e be hitting the proverbial before I be departing the hold. Assuming an escape exists.
Arrr!
When you live....
Use the GPS!
Assuming you're kitted out for it, set the GPS to OBS mode on the aid and dial up the tracks.
Tracking tolerance not good enough for the approaches but it will keep you out of strife if it all goes pear shaped. Even a little bitty handheld should be capable of keeping you away from the hills.
UTR.
Tracking tolerance not good enough for the approaches but it will keep you out of strife if it all goes pear shaped. Even a little bitty handheld should be capable of keeping you away from the hills.
UTR.
Two pages on how to conduct a missed approach!
Isn't this covered during training and the test?
Do we really need a Pprune Committee Meeting to work out what to do??? It's not rocket science!
Let go of Mummy's apron strings...!
Isn't this covered during training and the test?
Do we really need a Pprune Committee Meeting to work out what to do??? It's not rocket science!
Let go of Mummy's apron strings...!
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FTDK
So "fur'instance"...
The 025 track after HWS - intercept it or turn on passage and DR? Jepp/DAP give different impressions.
On another note (should this be separate thread?)...
What approach/holding design criteria lead to having a minimum holding pattern altitude higher than the 10NM MSA? Example.
Are the tolerances/allowances in the hold so great that they go outside 10NM? Is there some other reason?
If you were to use a holding altitude of 2500 in the case above you could shave 3 or 4 minutes off the approach procedure.
So "fur'instance"...
The 025 track after HWS - intercept it or turn on passage and DR? Jepp/DAP give different impressions.
On another note (should this be separate thread?)...
What approach/holding design criteria lead to having a minimum holding pattern altitude higher than the 10NM MSA? Example.
Are the tolerances/allowances in the hold so great that they go outside 10NM? Is there some other reason?
If you were to use a holding altitude of 2500 in the case above you could shave 3 or 4 minutes off the approach procedure.
FTDK
So "fur'instance"...
The 025 track after HWS - intercept it or turn on passage and DR? Jepp/DAP give different impressions.
1) The Airservices chart show an 80/260 degree procedure turn - after station passage turn left at Rate 1 onto 025 then turn back Rate 1 to the right onto 285. The Jepp chart shows a 45/180 degree procedure turn - after station passage turn left to make good a track of 060 for 1 min (Cat A & B) then rate 1 through 180 degrees to make good 240 then intercept 285.
On another note (should this be separate thread?)...
What approach/holding design criteria lead to having a minimum holding pattern altitude higher than the 10NM MSA? Example.
Are the tolerances/allowances in the hold so great that they go outside 10NM? Is there some other reason?
2) That's how I figure it.
If you were to use a holding altitude of 2500 in the case above you could shave 3 or 4 minutes off the approach procedure.
3) If you are worried about shaving time off an approach - stick with VFR - many of those who have gone before you had their life cycle abruptly ended by CFIT.
Fly the procedure like she is writ!
Dr
So "fur'instance"...
The 025 track after HWS - intercept it or turn on passage and DR? Jepp/DAP give different impressions.
1) The Airservices chart show an 80/260 degree procedure turn - after station passage turn left at Rate 1 onto 025 then turn back Rate 1 to the right onto 285. The Jepp chart shows a 45/180 degree procedure turn - after station passage turn left to make good a track of 060 for 1 min (Cat A & B) then rate 1 through 180 degrees to make good 240 then intercept 285.
On another note (should this be separate thread?)...
What approach/holding design criteria lead to having a minimum holding pattern altitude higher than the 10NM MSA? Example.
Are the tolerances/allowances in the hold so great that they go outside 10NM? Is there some other reason?
2) That's how I figure it.
If you were to use a holding altitude of 2500 in the case above you could shave 3 or 4 minutes off the approach procedure.
3) If you are worried about shaving time off an approach - stick with VFR - many of those who have gone before you had their life cycle abruptly ended by CFIT.
Fly the procedure like she is writ!
Dr
PPRuNeaholic
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Are the tolerances/allowances in the hold so great that they go outside 10NM? Is there some other reason?
Thus, if there's an obstacle beyond 15 NM from the navaid and it's higher than any of the obstacles within that radius, the pattern altitude will be higher than the MSA.
