I extracted the following quatation from Jeppesen ATC -"State Rules & Procedures" pages for UK.
"For non-JAR-OPS operators and those exempt from JAR-OPS 1.405: Under U.K. Legislation an aircraft, when making a descent to an aerodrome, shall not descend from a height of 1000ft or more above the aerodrome to a height less than 1000ft above the aerodrome if the relevant RVR at the aerodrome is at the time less than the specified minimum for landing, or
a. continue an “approach to landing” at any aerodrome by flying below the relevant specified DH, or
b. descend below the relevant specified MD unless, in either case, from such height the specified visual reference for landing is established and is maintained."
My question is regarding the following scenario: I am a non JAR-OPS operator and exempted from JAR-OPS 1.405. Planning a CAT 3 approach in UK. RVRs is better than required so descended below 1000 AGL. Suddenly RVR deteriorated below the minima. I continued to DH. By DH, there is no improvement in the last reported RVRs, however at DH I acquired the required visual reference for touchdown. Now, if I continue to land, is this going to be legal in the light of main paragraph and paragraph (a) above.
if the relevant RVR at the aerodrome is at the time less than the specified minimum for landing
Well, the RVR when you went below 1000' was above limits, so no problem there. You reached DA and had the required visual reference to land, so also no problem.
In JAR OPS, an approach ban only exist before the FAF (or point) therefore once passed that point you can continue to DA even if the RVR drop below limits, if at DA you have the correct visual references you can land irrespective of the reported RVR, if you don't have the required reference, go around.
"For non-JAR-OPS operators and those exempt from JAR-OPS 1.405: Under U.K. Legislation an aircraft, when making a descent to an aerodrome, shall not descend from a height of 1000ft or more above the aerodrome to a height less than 1000ft above the aerodrome if the relevant RVR at the aerodrome is at the time less than the specified minimum for landing, or
Having read your question, you have negotiated this obstacle: when you descended from above 1.000 ft HAA to below 1.000 ft HAA, RVR was better than limiting RVR. Next obstacle is to have sufficient visual reference at or above DH.
a. continue an “approach to landing” at any aerodrome by flying below the relevant specified DH, or
b. descend below the relevant specified MD
Please note that I have entered a linefeed at this position. The text beginning with "unless" is not a part of paragraph b., but covers both para's a. and b. Because, as you state, you have acquired the required visual reference before reaching DH, it is legal to land, provided that the req'd visual reference is maintained throughout. The fact that reported RVR had dropped to below required minimum RVR, after you were already below 1.000 ft HAA does not make your position below 1.000 ft HAA illegal. Just as during a take-off you decide to abort the take-off or to continue, you cannnot comeback on that decision after you have taken it. After the decision to descend below 1.000 ft HAA, the next decision is to continue below DH, or to go-around.
unless, in either case, from such height the specified visual reference for landing is established and is maintained."
RVRs were in excess of minimum for the approach allowing you to descend below 1000agl and continue to DH/MD.
You state "at DH I acquired the required visual reference for touchdown" and continue to land which is inline with the regs you quote. But if you dont acquire the lights then you would have to go around. Deciding to GA at DH the inertia will take you below minimums so adding at least 50feet to the DH is normal in our operation.
You state "at DH I acquired the required visual reference for touchdown" and continue to land which is inline with the regs you quote. But if you dont acquire the lights then you would have to go around. Deciding to GA at DH the inertia will take you below minimums so adding at least 50feet to the DH is normal in our operation.
What do you SOPs recommend?
rgds, GP
I have never heard of anyone adding 50 feet for inertia. Does anyone else do this?
I have heard instructors saying that main wheel contact with the runway may occur on the go around due to inertia!
We only add 50 feet when using a constant-angle approach down all the way down to MDA. Can't ever go below MDA without the stuff in sight, so 50 feet accounts for the go-around. (Even then, we don't apply the additive within the US, only to international airports where we can't be assured an obstacle survey has been completed) Never does it make any sense to add anything to a DH, that's what's it designed for in the first place.
Global Pilot - I'm afraid I'm with WorldDC10 at being surprised at your "add 50 feet". The Decision Height is actually determined on the assumption you will briefly descend through it during a go around - in the extreme case of a Cat 3 your main wheels can touch the runway. Contrast that with a non-precision approach where the assumption (and the instrument check ride standard) is that you do NOT descend below the MDA. In that case, it is quite common to add 50 feet to make sure you don't go below MDA - but it would be most unusual to do that on a DH.
In a normal 3 degree Cat 1 ILS with limiting RVR of 550 metres, you will NOT see the lights at 250 feet - you will need to keep going to 200 feet, or you'll not get in.
Not now but before I was flying with a JAR-OPS operator. So I am well aware what JAR-OPS 1 #1.405 cites about approach ban. That is exactly same what Mini-Jumbo mentions. However with my question, I intended to ask whether UK Rule particularly for Non Jar-Ops Operator (as I am curently employed) is slightly different than that. Because the format of the whole text I quoted gives me the idea that the last portion of the text starting with "Unless..." ("unless, in either case, from such height the specified visual reference for landing is established and is maintained." ) belongs only to paragrah (b). If it is so, then I commented (maybe because of inadequacy of my english): In UK, for a Non Jar Ops Operator, once got below 1000 feet (similiarly to Jar Ops Operator) pilot is stilll allowed to continue to DH (with expectation by that time an improvenent may occur). However (differently than Jar Ops operator) he/she it is not allowed to land as long as the reported RVR is below the mininima regardless the Non Jar-Ops Operator pilot acquires the required visual reference.
As EMIT did, if the paragraph (b) is broken up so that the part starting with "unless..." is also considered covering the paragrah (a), then I received my answer clearly.
Regarding the other comments (slightly veered off my question), I put the following extract from PAN-OPS FLIGHT PROCEDURES (DOC 8168) PART III. APPROACH PROCEDURES PARA 1.6.2 (Same can be found on JEPPESEN ATC Page 213). I guess it is a proper reference showing application of a certain amount of height correction is valid only when flying a "Stabilized Non Precision Approach". My company`s SOP suggests this as "50" feet.
.....The stabilized approach technique is also associated with operator-specified limits of speed, power, configuration and displacement at (a) specified height(s) designed to ensure the stability of the approach path and a requirement for an immediate go-around if these requirements are not met.
NOTE: 1. To achieve a constant descent gradient where stepdown fixes are specified, descent may be delayed until after passing the FAF, or the FAF crossed at an increased altitude/height. If a greater height is used, ATC clearance should be obtained to ensure separation. 2. When using the “stabilized approach” technique in a non-precision approach, the height/altitude at which the missed approach maneuver is initiated is a matter of pilot judgement based on the prevailing conditions and the overriding requirement to remain above the MDA/H. Where an operator specifies an advisory initiation altitude/ height (above MDA/H) based on average conditions, the associated visibility requirements should be based on the MDA/H and not the advisory altitude/height
The text "unless, in either case, from such height the specified visual reference for landing is established and is maintained."Applies to both a) and b). It states "in either case", which implies that in case a) or case b) you may only continue below DA or MDA when the visual requirements have been met.
Also we only add the 50' for non precision approaches where the glide path is manually checked. Gives a heads up prior to the MDH/MDA and saves 'spooning' the MDA/MDH.
1st I agree with mini-jumbo and others, I consider legal the submitted scenario.
Quote:
In JAR OPS, an approach ban only exist before the FAF (or point)
Jar-Ops 1.405 refers to OM or equivalent position. Where no OM or equivalent position exists the gate is referred to 1000 ft HAA. So the rule's sense could be to enclose non-JAR-OPS operators and those exempt from JAR-OPS 1.405 into Jar-Ops layout.
As an aside. One of the tech questions at ek as of late last year has a question with such a scenario. None of the answers were as per the approach ban mentioned here jar ops et al. Scenario interception of glide above platform(3000) and deterioation of rvr before faf. The nearest option was not to descend past the faf (publish platform 2500 meets glide.) Maintain platform and track loc to missedapproach point and go around.The other options were ludicrous
Now it made a few assumption about having a dme for map not a da etc etc but as ek are jar compliant was it just a badly constructed question or is there still a version of an icao apprach ban that is as per this question It was i believe constructed around a generic icao apprach ban, ie no 1000' or equivalent postion. Now the jar ban is an evolution of earlier regs vis vis faf or fap Anyone care to comment.
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), I put the following extract from PAN-OPS FLIGHT PROCEDURES (DOC 8168) PART III. APPROACH PROCEDURES PARA 1.6.2 (Same can be found on JEPPESEN ATC Page 213). I guess it is a proper reference showing application of a certain amount of height correction is valid only when flying a "Stabilized Non Precision Approach". My company`s SOP suggests this as "50" feet.
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