Use the ARP in emergency!

  • Hi again mates.
    Well this time let's see how we can use the ARP Fix of the airports that have a diagram in order to we have an almost precise "non precision" approach.
    This method can be used ONLY to airports that have a diagram and are a sigle RWY type with RWY length of 8,666 FT. Also the RWY should not have any displaced thresholds, like the new Kasteli airbase.
    So the sigle RWY type airports have RWY of 8,666 FT. The ARP Fix is perfectly in the middle of the RWY and over the centerline. That means that the ARP is exactly at 8,666/2=4,333 FT from each one RWY threshold or 4,333/6,076=0.71 NM -> 0.7 NM.
    Now for a 2.5 deg. descent for 4 NM we have 265FT/NM x 4NM= 1,060 FT.
    Finally our FAF will be at 4.7 DME from the ARP of the airport and at 1,060 FT above the RWY elevation with a 2.5 deg. slope.
    As an example i will use the Ifaistos airport in north Aegean sea.
    The imaginary case is that i was had a missed TACAN approach to RWY 03 on Ifaistos airport (the published one), and now i'm low on fuel and the nearest airport is the Megas Alexandros at north at 65 NM... Weather is bad with low fog that gives visibility of 0.7 NM (set from 0 FT to 4,255 FT).
    I have only fuel for one last approach and i'm already stressed in order to make it.
    Ifaistos airport has no ILS at both RWY's, so my last chance will be the usage of the ARP:
    FAF will be at 4.7 DME of ARP Fix, at 1,070 FT (1,060 FT + 10 FT RWY elevation) on ARP R-210 inbound with heading of 030 deg. for an approach to RWY 03.
    Below i'm exactly at FAF (4.7 DME of ARP Fix at 1,070 FT on ARP R-210 inbound) ready to start my 2.5 deg. descent


    Below i'm at ARP 1.3 DME (or at 1.3-0.7=0.6 NM from RWY threshold) and the RWY just be in sight (visibility set at 0.7 NM)


    Since i'm keeping the CDI centered at HSI i'm very well aligned with RWY, see below at ARP 55/61=0.9 DME (or at 0.9-0.7=0.2 NM from RWY threshold)


    Finally i had an easy and smooth touch down on RWY 03 of Ifaistos airport



    So let's summarize this method:
    - Use it ONLY at airports with single RWY that has length of 8,666 FT and NO displaced threshold! This airport must have a diagram to get the ARP GPS coordinates.
    - Altitude of FAF 1,060 FT + RWY elevation.
    - FAF at ARP 4.7 DME at calculated altitude on Radial of opposite RWY with an inbound course and a 2.5 deg. descent.
    - Touch down will be at 0.7 DME (43/61).
    - Be advised: DO NOT place the FPM over the STPT sign (diamond)! Place it over the 2.5 deg. pitch dive ladder!


    If you have any questions feel free to ask. My pleasure to help you.
    Nikos.

  • Hallo NICOS, my friend


    Thanks for pointing out this "self made emergency maneuver" to us.


    It's quiet a challenge!!


    Nevertheless: finding ourselves in one of those situations you described above leaves the feeling of not having planned properly... therefore I called it a "last ditch maneuver"


    Be advised that we do have (in the very most times) an ATC controller (callsign ZIRI) who would provide us with adequate GCA vectors and guidance so comply with a regular ASR approach (which normally serves down to a minimum of also 300 ft AGL like a TACAN usually does).


    So :


    If you find yourself in a missed approach from a perfectly flown TACAN (i.e. IFAISTOS 03) it must have been due to bad weather (below minimum)


    To use this Airport reference point as a GPS Nav Point might seem like a good alternative but leaves me "breathless" because also those GPS based approaches have to fulfil certain qualifications (you mentioned the obstacle clearance).
    My biggest concern is: WHO the hack will know wether these obstacle clearances will be fulfilled on a self guided GPS based Airport Reference Point approach if there is not a similar approach published which covers the same over ground track??


    It's just not legal to fly those approaches when they are not published!
    But I do see you point - it's a saving your "xss" maneuver which you can do in a game like BMS


    I would be scared to use it in real life !!! (IFR conditions, Vis below 2 NM and BKN or OVCST 002 or even worse)


    Second of all: you do refer to 030° as the RWY alignment of IFAISTOS - but of couse it's not written in any publication of IFAISTOS that this is really the case. Because it's BMS and a simulation with made-up RWY's I do guess that those RWY's which have no ILS are aligned accordingly (RWY-Name x 10 equals exact RWY course) but again - this maneuver is just applicable for this game on single RWY's with no overrun and standard length .....


    Third of all: for all your calculations you use 2.5° glideslope.....


    According to ICAO the "nominal" glideslope" is 3° and the old VASI - as in the case of IFAISTOS or the new PAPI system is always aligned to correspond with those glideslopes used at these airports.
    2.5° seems like an easy approach because the HUD shows 2.5 as a dashed line but it's not the usual glideslope the RWY's in BMS use. The glideslope has to be mentioned especially in any ILS approach - I do see 3° in CARDAK, DIAGORAS, KONYA, NEA ANCHIALOS... just to name a few
    This 3° glideslope also leads down to a touchdown at exactly 1000 ft behind the threshold - as I wrote you before - crossing the threshold at a safety hight of 40-50 ft


    These are the standards we at the 1st GW use - so in case we would use your "non precision approach based on ARP" on single RWY's with standard length we have to recalculate your figures to be used with a 3° glideslope.
    That's just a matter of mathematics and could easily be done.


    We do thank you for pointing out this alternative. :thumbup:


    Actually we do use sort of calculation like this presently for our ATC-guided ASR approach with the aid of F4AWACS out of the Online squadron collection.



    NICOS, we do appreciate and like your AEGEAN Theater very much and therefore we would like to "return" to this area later during 4.33


    We would be very interested to know, when AEGAEAN is "ready" for 4.33


    In the meantime have a nice holiday season and merry christmas to you, my friend


    SPARROW

  • Hi there my friend Peter.
    Well first of all, as i said and you also agree, it is "a last" chance in a very bad situation and only.
    Now after that, i can say to you these:
    - Don't use so "hard" and often the real life rules into BMS. I don't know if you know that BMS has a lot of limitations in its code that doesn't allow the fully application of all real life's rules. Example is all ILS in BMS have only 3 deg. slope, but in real life we have some different ones like 2.75 or even 2.5!
    Also the placement of PAPI and VASI isn't the perfect one in a lot of airports!
    Sometimes we must compromise with what we have and don't use real rules where we can't just apply them...
    - The fact that you usually have an ATC conroller is great! But that doesn't eliminate the possibility some time in some mission to really one (or more) Falcon pilots to be in a similar situation. So having this method in mind isn't at all bad. It will be just an extra last "weapon" in their hands and will be on them IF they would try it. I NEVER push the others to follow my methods/suggestions!!! I only share my personal ideas and only!
    - About your concern for "obstacle clearance", i already gave some examples at airstrips similar post. There it is very clear that at some airports/airstrips the method can be applied. A quick look at your proper Enroute Low Altitude chart and you may can have an idea IF you can use this method or not (like for Leros airstrip to RWY 18, for example that is super obvious that you can or to RWY 16 of Skiros airport).
    - I never say that this method is based to a real approved one. I just expressed one idea by me when everything else went wrong and bad :).
    - "for all your calculations you use 2.5° glideslope". Yes, this is completely right, for all the non precision approaches! Why not? Why i should put a pilot to an estimated 3 deg. slope while he has in his hands the 2.5 deg. dive line in HUD that can offer GREAT execution of the approach? Or this is not approved, means the usage of a 2.5 deg. slope? Of course and it is and instead with 3 deg. they BOTH are the "nominal" slopes! DO NOT confuse the ideal ILS 3 deg. glideslope with the non precision approaches of 2.5 deg. (or 3 deg. or even any other angled ones)! They are different approaches and i can tell you after personally i have study more than 400 REAL military procedures that the 2.5 deg. slope in the non precision approaches is also been heavily used!
    - I always respect and i will do that anyone else's methods and ideas. So please every time that you may read something by me, do not think that my target is to affect the others (or to force to follow) with my personal ideas/ways! Noway mate. I just share my knowledge and ideas and ONLY that, this is crystal clear :winki:.


    Last as already in our conversations, this is only my positions/reply to yours. No offending here or any "ego" reactions :thumbup: I always enjoy talking and change opinions with you!
    Thank you very much for your kindly words.
    I also wish you Merry Christmas with full of health. Also to all the rest friends of this forum.
    See you again my friend.


    Nikos.