OEI Missed Approach Procedure
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OEI Missed Approach Procedure
Under JAROPS – can operators use a OEI procedure if the criteria for Climb or Approach gradients cannot be met, in leu of the prescribed missed approach?
Also, are there examples of this under FAR Operations. That is – where the OEI operation do not meet the TERPS requirements, or special approach requirements, where a higher gradient is specified, and a OEI procedure is used to address any obstacle issues?
LOKE
Also, are there examples of this under FAR Operations. That is – where the OEI operation do not meet the TERPS requirements, or special approach requirements, where a higher gradient is specified, and a OEI procedure is used to address any obstacle issues?
LOKE
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You have to set higher standards to comply with the missed approach procedure.
There are cases (LPPR 17)where the missed approach has a climb gradient of 4.9% and if you are not able to comply with you have to advise the app .
There are lots of plates whre you see different minima for the same approach.
Some times it also happens because of higher accelaration altitude.
There are cases (LPPR 17)where the missed approach has a climb gradient of 4.9% and if you are not able to comply with you have to advise the app .
There are lots of plates whre you see different minima for the same approach.
Some times it also happens because of higher accelaration altitude.
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OEI procedures fulfill the requirement for an escape manoeuvre at certain aerodromes in the case of an engine failure after V1 when the aircraft is comitted to take-off.
Are you seeking to design a OEI procedure for a MAP procedure at a destination airfield?
If so, why would you fly to a destination with one engine out where the weather could require a MAP and that MAP is beyond the OEI capabilities of the aircraft even at the now lower weight and having the benefit of height and speed at the MAP?............why not divert to an alternate with better weather and less restrictive MAP gradients?
Are we talking about a remote airport that has no reasonable alternate with better weather or more shallow MAP gradients?
Regards,
DFC
Are you seeking to design a OEI procedure for a MAP procedure at a destination airfield?
If so, why would you fly to a destination with one engine out where the weather could require a MAP and that MAP is beyond the OEI capabilities of the aircraft even at the now lower weight and having the benefit of height and speed at the MAP?............why not divert to an alternate with better weather and less restrictive MAP gradients?
Are we talking about a remote airport that has no reasonable alternate with better weather or more shallow MAP gradients?
Regards,
DFC
Last edited by DFC; 16th Mar 2005 at 22:59.
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DFC:
“why would you fly to a destination with one engine out”
I read over my original message and it certainly wasn’t very clear – a few too many libations before I wrote it.
No – I was referring to commencing an approach where you are considering the possibility of an engine failure during the go-around and you have to meet Approach Climb gradients with an engine failure. Although there are certainly a considerably larger number of OEI takeoff procedures, there are a few OEI miss procedures where at, weights which would allow a reasonable payload, you wouldn’t make the Approach Climb Gradient.
The water gets distinctly muddier when – under FAR rules, though there is a requirement to consider obstacles clearances, (as opposed to simple gradients) there is no specific regulatory requirement for each individual flight for a missed approach. There is guideline FAA material that suggests it’s a damned good Idea – and I’m not at all arguing that – I think it is a good idea.
So – if due to obstacles in the missed path for the published procedure and a requirement to maintain a higher than normal gradient, operators will establish a OEI lateral path for the miss meeting similar obstacle clearances that are legally prescribed for the takeoff OEI procedures.
There is a suggestion of a higher minimum – but at times this can become very restrictive.
My question is – this is done in the US (FARs) - is there similar allowances for the Operator to design a OEI escape maneuver for such cases under JAROPS?
Appreciate your comments, sorry for the confusing first post. Appreciate any information that you can provide.
Regards,
Loke
“why would you fly to a destination with one engine out”
I read over my original message and it certainly wasn’t very clear – a few too many libations before I wrote it.
No – I was referring to commencing an approach where you are considering the possibility of an engine failure during the go-around and you have to meet Approach Climb gradients with an engine failure. Although there are certainly a considerably larger number of OEI takeoff procedures, there are a few OEI miss procedures where at, weights which would allow a reasonable payload, you wouldn’t make the Approach Climb Gradient.
The water gets distinctly muddier when – under FAR rules, though there is a requirement to consider obstacles clearances, (as opposed to simple gradients) there is no specific regulatory requirement for each individual flight for a missed approach. There is guideline FAA material that suggests it’s a damned good Idea – and I’m not at all arguing that – I think it is a good idea.
So – if due to obstacles in the missed path for the published procedure and a requirement to maintain a higher than normal gradient, operators will establish a OEI lateral path for the miss meeting similar obstacle clearances that are legally prescribed for the takeoff OEI procedures.
There is a suggestion of a higher minimum – but at times this can become very restrictive.
My question is – this is done in the US (FARs) - is there similar allowances for the Operator to design a OEI escape maneuver for such cases under JAROPS?
Appreciate your comments, sorry for the confusing first post. Appreciate any information that you can provide.
Regards,
Loke
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As far as I am aware if yur engine fails at the DA on say an ILS you are;
200+ feet above the runway
At a landing weight not a take-off weight
Flying with lots of momentum (although landing flap does not help); and
probably some thousands of metres before the end of the TODA.
If you can't clear obstacles in the MAP from that position I think the only option is to increase the minima i.e. go arround from a higher position.
However, there could be the case of you having to go-around just as your touchdown (upset / runway infringement etc) and where would you go then?
One must remember that the MAP procedure not only gets you back to the hold without hitting any obstacles but it also keeps you within a defined profile for ATC separation purposes.
Can you tell me what airfield/procedure you are thinking of and I will have a look.
regards,
DFC
200+ feet above the runway
At a landing weight not a take-off weight
Flying with lots of momentum (although landing flap does not help); and
probably some thousands of metres before the end of the TODA.
If you can't clear obstacles in the MAP from that position I think the only option is to increase the minima i.e. go arround from a higher position.
However, there could be the case of you having to go-around just as your touchdown (upset / runway infringement etc) and where would you go then?
One must remember that the MAP procedure not only gets you back to the hold without hitting any obstacles but it also keeps you within a defined profile for ATC separation purposes.
Can you tell me what airfield/procedure you are thinking of and I will have a look.
regards,
DFC
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There are two scenarios here. Approach Go-around climb and landing GA climb.
The approach GA assumes a GA at DA/MDA and the landing GA is from a baulked landing.
If a missed approach doesn't state otherwise a min gradient of 2.5% is required. The appr GA assumes OEI configuration and the LDG GA assumes all eng operative configuration.
If you are unable to achieve 2.5% appr GA(or the min % as stated and the appr chart- it could be higher) you must use a higher minima.
If you are unable to achieve the LDG GA % (more likely than Appr because we are now assuming all eng op config!) you can follow a SID if you have the performance (would have to check T/O perf) fly an engine out emergency turn (if published for that runway) or fly a visual escape manoeuvre.
Obviously at 50ft if we GA and an engine fails we don't have any time to think about this!! I've been flying 75/76 for 10 years and have NEVER thought about or briefed this scenario so I count myself very lucky that I never found myself in this situation. I now think AND brief about this everytime it could save our lives one day.
Check this
http://www.jaa.nl/section1/jars/508120.pdf PAGE 65
I forgot to say, DALAMAN (LTBS) has a DA on R/W 01 of 210\' (200) if you can achieve 8.0% and a DA of 1210\' (1000\') if you can achieve 2.5%. A 737-800 at 65000KG at 30\'C can achieve approx 3.6% appr clb GA
The approach GA assumes a GA at DA/MDA and the landing GA is from a baulked landing.
If a missed approach doesn't state otherwise a min gradient of 2.5% is required. The appr GA assumes OEI configuration and the LDG GA assumes all eng operative configuration.
If you are unable to achieve 2.5% appr GA(or the min % as stated and the appr chart- it could be higher) you must use a higher minima.
If you are unable to achieve the LDG GA % (more likely than Appr because we are now assuming all eng op config!) you can follow a SID if you have the performance (would have to check T/O perf) fly an engine out emergency turn (if published for that runway) or fly a visual escape manoeuvre.
Obviously at 50ft if we GA and an engine fails we don't have any time to think about this!! I've been flying 75/76 for 10 years and have NEVER thought about or briefed this scenario so I count myself very lucky that I never found myself in this situation. I now think AND brief about this everytime it could save our lives one day.
Check this
http://www.jaa.nl/section1/jars/508120.pdf PAGE 65
I forgot to say, DALAMAN (LTBS) has a DA on R/W 01 of 210\' (200) if you can achieve 8.0% and a DA of 1210\' (1000\') if you can achieve 2.5%. A 737-800 at 65000KG at 30\'C can achieve approx 3.6% appr clb GA
Yes this is a topic that is rather neglected by both pilots and the Authorities who design instrument approaches.
Here in Australia the regulations state:
"In the event that a missed approach is initiated prior to arriving at the MAPT (Missed Approach Point), pilots must fly the aircraft to the MAPT and then follow the missed approach procedure."
They mention nothing about initiating a missed approach beyond the MAPT and below the Approach Minima. It seems you are left to your own devices.
There are plenty of reasons why you might need to initiate a missed approach beyond the MAPT.
1) Subsequently loosing the required visibility.
2) Excessive crosswind/ downwind.
3) Windshear
4) Runway occupied by:
a) departing aircraft taking too long to initiate take-off roll.
b) previous arriving aircaft taking too long to vacate runway.
c) runway incursion by taxiing aircraft.
And there is absolutely no reason why an engine failure could not occur at that time. Sudden application of go-around thrust, bird ingestation. etc.
Along the lines of what Winston said, just imagine the scenario when you are taking-off from the same runway. If your company has published a special procedure to follow in the event of an engnie failure during the take-off, follow that procedure. Remember too that the clean-up/ acceleration altitude might be higher than normal. If there is no special procedure to follow and you are free to accept a radar heading (such as runway heading!) I would recommend you simply tracking straight ahead on the runway extended centreline and telling ATC what you are doing. I would be maintaining this tracking until reaching radar lowest safe altitude or MSA.
To answer you question LOKE, well infact I can't anwer your question. However I imagine your regulations might be as uninformative as ours on this subject.
Here in Australia the regulations state:
"In the event that a missed approach is initiated prior to arriving at the MAPT (Missed Approach Point), pilots must fly the aircraft to the MAPT and then follow the missed approach procedure."
They mention nothing about initiating a missed approach beyond the MAPT and below the Approach Minima. It seems you are left to your own devices.
There are plenty of reasons why you might need to initiate a missed approach beyond the MAPT.
1) Subsequently loosing the required visibility.
2) Excessive crosswind/ downwind.
3) Windshear
4) Runway occupied by:
a) departing aircraft taking too long to initiate take-off roll.
b) previous arriving aircaft taking too long to vacate runway.
c) runway incursion by taxiing aircraft.
And there is absolutely no reason why an engine failure could not occur at that time. Sudden application of go-around thrust, bird ingestation. etc.
Along the lines of what Winston said, just imagine the scenario when you are taking-off from the same runway. If your company has published a special procedure to follow in the event of an engnie failure during the take-off, follow that procedure. Remember too that the clean-up/ acceleration altitude might be higher than normal. If there is no special procedure to follow and you are free to accept a radar heading (such as runway heading!) I would recommend you simply tracking straight ahead on the runway extended centreline and telling ATC what you are doing. I would be maintaining this tracking until reaching radar lowest safe altitude or MSA.
To answer you question LOKE, well infact I can't anwer your question. However I imagine your regulations might be as uninformative as ours on this subject.
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Looking at the idea of using the OEI take-off procedure to permit operations at such weights that it is not possible to meet the MAP required obstacle clearance;
The OEI procedure starts at the end of the TODA and only considders obtsacles 60m + (wingspan/2) each side of track initially - not very far for a bizjet!. This area expands with increasing distance from the end of the TODA however, it is based on the idea that the pilot will be on or very close to the runway centerline at the end of the TODR.
The whole procedure is based on having the aircraft very accurately positioned and only 35ft above obstacles!
How can you acheive the same level of positional accuracy using the guidance provided (if any) during the MAP?
Basically I expect that you will have to re-survey the area each side of the OEI area and that will probably result in the obstacles that affect the MAP procedure being involved..........thus you may gain very little because I expect the procedure designer would have done their best to design the MAP that permits the lowest possible MAP gradients within the constraints of the MAP procedure.
Even if you do come up with your own single engine MAP procedure that has an advantage, ATC may object because the last thing they want is an aircraft with an emergency heading directly out of their protected airspace or directly at other traffic.........they will probably say - use lower weights so that you can meet the MAP requirements!
------------
ICAO 8168 says;
It is emphasised that a missed approach procedure which is based on the normal climb gradient of 2.5% cannot be used by all aeroplanes when operating at or close to maximum certified gross mass and engine out conditions. The operation of such aeroplanes needs special considderation at aerodromes which are critical due to obstacles in the missed approach area and may result in a special procedure being established with a possible increase in the DA(DH) or MDA(MDH).
That seems to indicate that the "special procedure" is permitted but I bet that the authorities would require such procedures to be approved and see above for obstacle clearance.
Regards,
DFC
The OEI procedure starts at the end of the TODA and only considders obtsacles 60m + (wingspan/2) each side of track initially - not very far for a bizjet!. This area expands with increasing distance from the end of the TODA however, it is based on the idea that the pilot will be on or very close to the runway centerline at the end of the TODR.
The whole procedure is based on having the aircraft very accurately positioned and only 35ft above obstacles!
How can you acheive the same level of positional accuracy using the guidance provided (if any) during the MAP?
Basically I expect that you will have to re-survey the area each side of the OEI area and that will probably result in the obstacles that affect the MAP procedure being involved..........thus you may gain very little because I expect the procedure designer would have done their best to design the MAP that permits the lowest possible MAP gradients within the constraints of the MAP procedure.
Even if you do come up with your own single engine MAP procedure that has an advantage, ATC may object because the last thing they want is an aircraft with an emergency heading directly out of their protected airspace or directly at other traffic.........they will probably say - use lower weights so that you can meet the MAP requirements!
------------
ICAO 8168 says;
It is emphasised that a missed approach procedure which is based on the normal climb gradient of 2.5% cannot be used by all aeroplanes when operating at or close to maximum certified gross mass and engine out conditions. The operation of such aeroplanes needs special considderation at aerodromes which are critical due to obstacles in the missed approach area and may result in a special procedure being established with a possible increase in the DA(DH) or MDA(MDH).
That seems to indicate that the "special procedure" is permitted but I bet that the authorities would require such procedures to be approved and see above for obstacle clearance.
Regards,
DFC
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DFC:
“That seems to indicate that the "special procedure" is permitted but I bet that the authorities would require such procedures to be approved and see above for obstacle clearance.”
Yes – this is what I was referring to. In the US there are a few special approaches which require a very steep gradient for the MAP. As one fellow put it – “you couldn’t make that in an empty 757 on a cold day” – this referring to engine out procedures. There are approaches with lower gradients & higher Minimums but to get a lower minimum, air carrier performance engineers create a OEI MAP. This of course is similar to the OEI Takeoff procedure and likely uses the same lateral path as it is probably the most obstacle free path.
So – my question is – are there examples of this under JAROPS?
LK
“That seems to indicate that the "special procedure" is permitted but I bet that the authorities would require such procedures to be approved and see above for obstacle clearance.”
Yes – this is what I was referring to. In the US there are a few special approaches which require a very steep gradient for the MAP. As one fellow put it – “you couldn’t make that in an empty 757 on a cold day” – this referring to engine out procedures. There are approaches with lower gradients & higher Minimums but to get a lower minimum, air carrier performance engineers create a OEI MAP. This of course is similar to the OEI Takeoff procedure and likely uses the same lateral path as it is probably the most obstacle free path.
So – my question is – are there examples of this under JAROPS?
LK
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Blip,
Interesting subject, worth a response.
Yes to the former but not to the latter. Instrument approach design is based on transition from an unacceptable visibility to a position where a specified minimum visibility should allow you to safely land the aeroplane. It is a descent plan. The international standards only consider all engine operations (AEO) in normal configurations because there are far too many variables to consider for OEI or other abnormal operations. It is not neglect, it is a choice between delivering a result or nothing.
The design criteria are that you go around before or at the MAPT unless you can safely land. The designs are 3D designs that require a starting position (lat/long/alt) and MApp gradient to be of any use. How many possibilities would you consider for other options while trying to provide a useful minima?
Any time you have to do something outside the design criteria, you are left to your own devices because you are the person who knows the likely circumstances, possible failures, performance consequences, personal capabilities, etc.
Yes, all that is true. It also should form the basis of your plan for safe flight. In many ways, the instrument approach design is now irrelevant, since you are flying outside the design parameters. You now have to get the aeroplane back to the MAPT if you wish to use the information that the MApp procedure provides. So now you have to have a climb plan to get there. That involves totally different obstacle considerations and protected airspace options that are totally unrelated to the approach design.
NO, NO, NO - unless you can position the aeroplane within the confines of the take-off splay some 2 km away (for CAO 20.7.1B within 76.2m or 90m either side of centreline at the end of the TODA) given crosswind, yaw, control issues etc then the special departure procedure (SDP) is potentially very unsafe. You need to consider more broadly protected airspace that applies to where you are commencing your go-round.
That is certainly true, particularly as the SDP acceleration altitude is only valid if you are within the splay and not closer to the obstacles than for the take-off case. ICAO Instrument procedure design does not allow for level acceleration segments - another complication for OEI MApp planning!!
So, we have touched on two very separate issues. One is OEI MApp planning and the other is contingencies during descent below MDA/DA. They are both complex subjects with many variables.
and LOKE,
May I suggest you need to reconsider your attitude to the inconvenience of raising the minima to improve the safety of the MApp flight path - the professional decision is accept that there are times when the weather precludes you from going to certain places. Should you decide otherwise, then you become the person who may be required to defend your acceptance of the risk.
Stay Alive,
Interesting subject, worth a response.
Yes this is a topic that is rather neglected by both pilots and the Authorities who design instrument approaches.
Here in Australia the regulations state:
"In the event that a missed approach is initiated prior to arriving at the MAPT (Missed Approach Point), pilots must fly the aircraft to the MAPT and then follow the missed approach procedure."
They mention nothing about initiating a missed approach beyond the MAPT and below the Approach Minima. It seems you are left to your own devices.
"In the event that a missed approach is initiated prior to arriving at the MAPT (Missed Approach Point), pilots must fly the aircraft to the MAPT and then follow the missed approach procedure."
They mention nothing about initiating a missed approach beyond the MAPT and below the Approach Minima. It seems you are left to your own devices.
Any time you have to do something outside the design criteria, you are left to your own devices because you are the person who knows the likely circumstances, possible failures, performance consequences, personal capabilities, etc.
There are plenty of reasons why you might need to initiate a missed approach beyond the MAPT.
1) Subsequently lo(o)sing the required visibility.
2) Excessive crosswind/ downwind.
3) Windshear
4) Runway occupied by:
a) departing aircraft taking too long to initiate take-off roll.
b) previous arriving aircraft taking too long to vacate runway.
c) runway incursion by taxiing aircraft.
And there is absolutely no reason why an engine failure could not occur at that time. Sudden application of go-around thrust, bird ingestation. etc.
1) Subsequently lo(o)sing the required visibility.
2) Excessive crosswind/ downwind.
3) Windshear
4) Runway occupied by:
a) departing aircraft taking too long to initiate take-off roll.
b) previous arriving aircraft taking too long to vacate runway.
c) runway incursion by taxiing aircraft.
And there is absolutely no reason why an engine failure could not occur at that time. Sudden application of go-around thrust, bird ingestation. etc.
Along the lines of what Winston said, just imagine the scenario when you are taking-off from the same runway. If your company has published a special procedure to follow in the event of an engnie failure during the take-off, follow that procedure.
Remember too that the clean-up/ acceleration altitude might be higher than normal.
So, we have touched on two very separate issues. One is OEI MApp planning and the other is contingencies during descent below MDA/DA. They are both complex subjects with many variables.
and LOKE,
There is a suggestion of a higher minimum – but at times this can become very restrictive.
Stay Alive,
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4dogs:
“and LOKE,
quote:
________________________________________
There is a suggestion of a higher minimum – but at times this can become very restrictive.
________________________________________
May I suggest you need to reconsider your attitude to the inconvenience of raising the minima to improve the safety of the MApp flight path - the professional decision is accept that there are times when the weather precludes you from going to certain places. Should you decide otherwise, then you become the person who may be required to defend your acceptance of the risk.
Stay Alive,”
Perhaps I did not explain myself very clearly. These are not my attitudes – these are published special approaches with OEI procedures practiced by airlines in the US. I was simply asking if there was an option under JAROPS for an air carrier to create a OEI procedure for an approach when the higher than normal miss gradient cannot be made.
I’m not suggesting that a pilot make up their own OEI procedure or that an airline operate illegally. Once again – this has nothing to do with my attitude. I’m talking about legalities and procedures not feelings and wags at performance.
Regards,
LK
“and LOKE,
quote:
________________________________________
There is a suggestion of a higher minimum – but at times this can become very restrictive.
________________________________________
May I suggest you need to reconsider your attitude to the inconvenience of raising the minima to improve the safety of the MApp flight path - the professional decision is accept that there are times when the weather precludes you from going to certain places. Should you decide otherwise, then you become the person who may be required to defend your acceptance of the risk.
Stay Alive,”
Perhaps I did not explain myself very clearly. These are not my attitudes – these are published special approaches with OEI procedures practiced by airlines in the US. I was simply asking if there was an option under JAROPS for an air carrier to create a OEI procedure for an approach when the higher than normal miss gradient cannot be made.
I’m not suggesting that a pilot make up their own OEI procedure or that an airline operate illegally. Once again – this has nothing to do with my attitude. I’m talking about legalities and procedures not feelings and wags at performance.
Regards,
LK
Last edited by LOKE; 25th Mar 2005 at 19:59.
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Can you provide an example in the US of a published instrument approach that an airline has constructed a special OEI MAP procedure for so that they can use lower minima?
Let me know the airport and approach- I can get the chart and please verbally describe the OEI procedure for the MAP with the minima used.
I can then look at what you are asking for and see if I have ever come across anything similar elsewhere.
Regards,
DFC
Let me know the airport and approach- I can get the chart and please verbally describe the OEI procedure for the MAP with the minima used.
I can then look at what you are asking for and see if I have ever come across anything similar elsewhere.
Regards,
DFC
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DFC
I may have unintentionally misled you. These are “special” approaches and though they are published for the air carriers that are authorized to use them, they are not available to the general public. The one that springs to mind is the “Silver” approach into Reno, Nevada ILS Rwy 16R. The standard mins are set at 928’ AGL with no restrictions on the miss.
The Silver ILS goes down to 200’ AGL but there is an approximate 8% climb gradient required for the miss (straight out climb to 6,000 above the miss altitude). As I mentioned – one Performance Engineer said about the only twin jet that could make that single engine is an empty 757 on a cold day.
So air carriers provide a OEI procedure which goes straight for a couple of miles, then makes about a 220° turn around a nasty protuberance called “Rattlesnake Hill” then back over the north end of the field up a valley.
The OEI miss procedure flies over the same track provided for the OEI takeoff procedure for the same runway – as this is the least obstacle rich environment around. The same obstacle clearance criteria are used as the takeoff procedure except that the aircraft configuration is defined by the Approach Climb limitations of FAR 25.
I believe there are several of these types of approaches in Colorado (obviously the altitude is a major performance factor here) and I have been told that there are lots in South America but I cannot provide examples.
I suspect you and I are beyond quibbling over the word "attitude" so I'm not going to be drawn into that - we can just chalk it up to my poor writing skills.
Perhaps someone else who has examples can chime in. US, Australia, Asia?
Thanks for any info,
LK
I may have unintentionally misled you. These are “special” approaches and though they are published for the air carriers that are authorized to use them, they are not available to the general public. The one that springs to mind is the “Silver” approach into Reno, Nevada ILS Rwy 16R. The standard mins are set at 928’ AGL with no restrictions on the miss.
The Silver ILS goes down to 200’ AGL but there is an approximate 8% climb gradient required for the miss (straight out climb to 6,000 above the miss altitude). As I mentioned – one Performance Engineer said about the only twin jet that could make that single engine is an empty 757 on a cold day.
So air carriers provide a OEI procedure which goes straight for a couple of miles, then makes about a 220° turn around a nasty protuberance called “Rattlesnake Hill” then back over the north end of the field up a valley.
The OEI miss procedure flies over the same track provided for the OEI takeoff procedure for the same runway – as this is the least obstacle rich environment around. The same obstacle clearance criteria are used as the takeoff procedure except that the aircraft configuration is defined by the Approach Climb limitations of FAR 25.
I believe there are several of these types of approaches in Colorado (obviously the altitude is a major performance factor here) and I have been told that there are lots in South America but I cannot provide examples.
I suspect you and I are beyond quibbling over the word "attitude" so I'm not going to be drawn into that - we can just chalk it up to my poor writing skills.
Perhaps someone else who has examples can chime in. US, Australia, Asia?
Thanks for any info,
LK
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DFC:
"The standard mins are set at 928’ AGL with no restrictions on the miss."
Damn I gotta stop drinkin when I post - I made a mistake on the minimums for the standard ILS at RNO. It's actuall 1100' (DH) & 4 miles VIS. The Silver is 200' DH & 1/2 mile VIS.
Considerable difference. There is also another special ILS with a 600' DH and though it does require a steepre than normal miss, it is not as steep as the 8% required on the Silver.
LK
"The standard mins are set at 928’ AGL with no restrictions on the miss."
Damn I gotta stop drinkin when I post - I made a mistake on the minimums for the standard ILS at RNO. It's actuall 1100' (DH) & 4 miles VIS. The Silver is 200' DH & 1/2 mile VIS.
Considerable difference. There is also another special ILS with a 600' DH and though it does require a steepre than normal miss, it is not as steep as the 8% required on the Silver.
LK
4dogs. Thanks for the input.
Well what other choices do I really have 4dogs?
If I'm rejecting the landing (going-around at very low level and I'm lined up with the runway) what else am I going to do other than track the runway centreline as best I can (it's not too difficult with a look out the window and a track box on my HSI.) and then go from there.
I mean anything I do from that position is potentially unsafe because as you have admitted, the scenario is not considered during the design of the approach and yet it is so obviously an issue that needs to be considered by the pilot before commencing the approach.
Trying to regain the published missed approach tracking AND minimum climb profile is surely MORE dangerous than what I propose.
Regarding protected airspace around the airport, what do I have to choose from?
I've got:
a) a highly detailed surveyed area commencing from the departure end of the runway expanding as you say from 90 metres either side of the runway centreline at around 7 degrees either side as per CAO 20.7.1B,
b) circling minima inside the circling area,
c)MSA
Now if I am going-around at 100ft, 50ft, 10ft AGL, and lined up with the runway, initially the surveyed area ahead of me will offer me the best protection, then if I am lucky, I might reach the circling minima while still inside the circling area. Fine. If I am still visual AND can maintain the aircraft inside the circling area I can level off and try another circling approach. If that doesn't appeal to me, I can continue the CAO 20.7.1B tracking until I reach the MSA or Radar LSALT.
Well I know that the survey was done with the takeoff in mind however I can't see a better option. If I turn, I'm turning into the unknown, and reducing my climb performance. I might be in the circling area but so what? I'm so much below the circling minima that... I hardly need to finish this sentance.
4dogs I'd appreciate you telling me what you consider to be the safest option following a low lever go-around.
Thankyou.
quote:
Along the lines of what Winston said, just imagine the scenario when you are taking-off from the same runway. If your company has published a special procedure to follow in the event of an engnie failure during the take-off, follow that procedure.
NO, NO, NO - unless you can position the aeroplane within the confines of the take-off splay some 2 km away (for CAO 20.7.1B within 76.2m or 90m either side of centreline at the end of the TODA) given crosswind, yaw, control issues etc then the special departure procedure (SDP) is potentially very unsafe. You need to consider more broadly protected airspace that applies to where you are commencing your go-round.
Along the lines of what Winston said, just imagine the scenario when you are taking-off from the same runway. If your company has published a special procedure to follow in the event of an engnie failure during the take-off, follow that procedure.
NO, NO, NO - unless you can position the aeroplane within the confines of the take-off splay some 2 km away (for CAO 20.7.1B within 76.2m or 90m either side of centreline at the end of the TODA) given crosswind, yaw, control issues etc then the special departure procedure (SDP) is potentially very unsafe. You need to consider more broadly protected airspace that applies to where you are commencing your go-round.
If I'm rejecting the landing (going-around at very low level and I'm lined up with the runway) what else am I going to do other than track the runway centreline as best I can (it's not too difficult with a look out the window and a track box on my HSI.) and then go from there.
I mean anything I do from that position is potentially unsafe because as you have admitted, the scenario is not considered during the design of the approach and yet it is so obviously an issue that needs to be considered by the pilot before commencing the approach.
Trying to regain the published missed approach tracking AND minimum climb profile is surely MORE dangerous than what I propose.
Regarding protected airspace around the airport, what do I have to choose from?
I've got:
a) a highly detailed surveyed area commencing from the departure end of the runway expanding as you say from 90 metres either side of the runway centreline at around 7 degrees either side as per CAO 20.7.1B,
b) circling minima inside the circling area,
c)MSA
Now if I am going-around at 100ft, 50ft, 10ft AGL, and lined up with the runway, initially the surveyed area ahead of me will offer me the best protection, then if I am lucky, I might reach the circling minima while still inside the circling area. Fine. If I am still visual AND can maintain the aircraft inside the circling area I can level off and try another circling approach. If that doesn't appeal to me, I can continue the CAO 20.7.1B tracking until I reach the MSA or Radar LSALT.
NO, NO, NO - unless you can position the aeroplane within the confines of the take-off splay some 2 km away (for CAO 20.7.1B within 76.2m or 90m either side of centreline at the end of the TODA)...
4dogs I'd appreciate you telling me what you consider to be the safest option following a low lever go-around.
Thankyou.
Last edited by Blip; 28th Mar 2005 at 11:19.
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I hear what you're saying blip and, apart from being a procedure designer, I'm also a pilot so I've confronted all of the same problems. And I've done it at places where there is absolutely no guarantee of obstacle clearance beyond the surveyed area of the Type "A" chart. In fact, there's a very BIG chance of a big fat obstacle just beyond the surveyed limit!
Talk about being between a rock and a bloody hard place!
But 4dogs is right about the design criteria. There's always a chance that the sorts of issues that have already been canvassed here will disrupt an approach at DA/MDA, when you're committed to a landing. Because of this, your company should have a procedure to deal with it.
I know that statement is a cop out, but bear in mind that the published DA/MDA is the absolute minima. The lowest altitude that can be provided. Some operators impose higher DA/MDA through the use of approach charts that are tailored to their own requirements.
At the end of the day, safety is paramount. There are, usually, many lives that depend on official procedures, company SOPs and the pilot's own instinct for survival.
Talk about being between a rock and a bloody hard place!
But 4dogs is right about the design criteria. There's always a chance that the sorts of issues that have already been canvassed here will disrupt an approach at DA/MDA, when you're committed to a landing. Because of this, your company should have a procedure to deal with it.
I know that statement is a cop out, but bear in mind that the published DA/MDA is the absolute minima. The lowest altitude that can be provided. Some operators impose higher DA/MDA through the use of approach charts that are tailored to their own requirements.
At the end of the day, safety is paramount. There are, usually, many lives that depend on official procedures, company SOPs and the pilot's own instinct for survival.
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Blip,
There is no single solution to what we agree is a very vexed issue. What may work in one set of circumstances may not work in another.
I did say NO unless you can....
It depends on the type of machinery you fly, how many motors are running and whether you can look out the window or whether it is wise to do so. From my observations, large aircraft go-rounds involve high nose attitudes that obscure the view plus a need to fly very accurately on the clocks. If it is OEI, then one can expect lots of yaw and a fair bit of lateral translation. If it is dark, you will be lucky to see anything outside until you are reconfigured. If, OTOH, you a flying a little aeroplane, then you should be climbing for all that it is worth while still within the flight strip/aerodrome perimeter.
The OLS for the runway will provide you with some immediate protection from very low level. The take-off portion of the OLS ends up looking much like the take-off splay for CAO 20.7.1B, although it might be wider. My major concern is the tendency to rely on an acceleration altitude that is totally dependent upon the design of the SDP and its containment area to be safe. That is the real NO NO.
One thing I always look for is any missed approach procedure that relates to the approach end of the runway to which I am circling, since it most certainly will provide me with an option far better than me making it up at the time. I should be aware of the gradients required and available to me, hence I should know if I can get back to that missed approach obstacle clear path from below if required.
If there is nothing designed, then my options are fewer so my decisions must be made earlier if possible. Those decision need to relate to minimising the chances of going around due to detectable causes such as weather, lights, flight path management, etc. If not possible then I need to know where the problem terrain is, so I weigh up the straight ahead versus turn options - and yes, I will turn within the circling area below the circling minima provided I am in deep shet already for straight ahead, am still climbing and I have achieved at least half the MOC height...
And in our less than perfect world, there are just some days when you wished you stayed in bed.
All of which reinforces what is behind CAR(88) 218 and 219 for planning and observation. Remember the 6 Ps!
Stay Alive,
There is no single solution to what we agree is a very vexed issue. What may work in one set of circumstances may not work in another.
If I'm rejecting the landing (going-around at very low level and I'm lined up with the runway) what else am I going to do other than track the runway centreline as best I can (it's not too difficult with a look out the window and a track box on my HSI.) and then go from there. (my emphasis)
It depends on the type of machinery you fly, how many motors are running and whether you can look out the window or whether it is wise to do so. From my observations, large aircraft go-rounds involve high nose attitudes that obscure the view plus a need to fly very accurately on the clocks. If it is OEI, then one can expect lots of yaw and a fair bit of lateral translation. If it is dark, you will be lucky to see anything outside until you are reconfigured. If, OTOH, you a flying a little aeroplane, then you should be climbing for all that it is worth while still within the flight strip/aerodrome perimeter.
The OLS for the runway will provide you with some immediate protection from very low level. The take-off portion of the OLS ends up looking much like the take-off splay for CAO 20.7.1B, although it might be wider. My major concern is the tendency to rely on an acceleration altitude that is totally dependent upon the design of the SDP and its containment area to be safe. That is the real NO NO.
One thing I always look for is any missed approach procedure that relates to the approach end of the runway to which I am circling, since it most certainly will provide me with an option far better than me making it up at the time. I should be aware of the gradients required and available to me, hence I should know if I can get back to that missed approach obstacle clear path from below if required.
If there is nothing designed, then my options are fewer so my decisions must be made earlier if possible. Those decision need to relate to minimising the chances of going around due to detectable causes such as weather, lights, flight path management, etc. If not possible then I need to know where the problem terrain is, so I weigh up the straight ahead versus turn options - and yes, I will turn within the circling area below the circling minima provided I am in deep shet already for straight ahead, am still climbing and I have achieved at least half the MOC height...
And in our less than perfect world, there are just some days when you wished you stayed in bed.
All of which reinforces what is behind CAR(88) 218 and 219 for planning and observation. Remember the 6 Ps!
Stay Alive,
