Originally Posted by
Giannipilota
Caro flydive1 - "Mantenere la pista in vista non è sempre possibile o richiesto." , non sono daccordo con te ( o con chi ha scritto ciò nei manuali che utilizzi ), la pista deve essere sempre in vista. E' l'assunto iniziale di ICAO e FAA; o se preferisci, il principio fondamentale di tale procedura IFR.
Quindi è sempre richiesto, e se non è possibile: si deve riattaccare.
Il problema è proprio che sappiamo già che riattaccheremo, 2400 metri non sono sufficienti e il mio intento è far giungere alle 3 Authority questo messaggio.
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Conosco più di un aeroporto dove i "prescribed track" rendono impossibile mantenere la pista in vista impossibile.
Esistono anche altri casi dove non è possibile.
Non centrano i manuali di compagnia e chi li ha scritti.
Da un post precedente:
Originally Posted by
RaymundoNavarro
Per quel che può servire.....
Premesso che concordo con il concetto di Nick1: concetto di minima il minimo legale sopra al quale si lascia alla discrezionalità del Pilota la possibilità di provare un avvicinamento.
Mi permetto di riportare la CRD che venne emessa a seguito della NPA relativamente alla pubblicazione delle minime di circling:
GM1-NCC.OP.112 Aerodrome operating minima — circling operations with aeroplanes
SUPPLEMENTAL INFORMATION
1) The purpose of this Guidance Material is to provide operators with supplemental information regarding the application of aerodrome operating minima in relation to circling approaches
2) Conduct of flight — general:
a) the MDH and obstacle clearance height (OCH) included in the procedure are referenced to aerodrome elevation;
b) the MDA is referenced to mean sea level;
c) for these procedures, the applicable visibility is the meteorological visibility; and
d) operators should provide tabular guidance of the relationship between height above threshold and the in-flight visibility required to obtain and sustain visual contact during the circling manoeuvre.
3) Instrument approach followed by visual manoeuvring (circling) without prescribed tracks:
a) When the aeroplane is on the initial instrument approach, before visual reference is stabilised, but not below MDA/H — the aeroplane should follow the corresponding instrument approach procedure until the appropriate instrument MAPt is reached.
b) At the beginning of the level flight phase at or above the MDA/H, the instrument approach track determined by radio navigation aids, GNSS, or ILS, MLS, GLS or PAR should be maintained until the pilot:
i . estimates that, in all probability, visual contact with the runway of intended landing or the runway environment will be maintained during the entire circling procedure;
ii . estimates that the aeroplane is within the circling area before commencing circling; and
iii . is able to determine the aeroplane’s position in relation to the runway of intended landing with the aid of the appropriate external references.
c) When reaching the published instrument MAPt and the conditions stipulated in 3.b. are unable to be established by the pilot, a missed approach should be carried out in accordance with that instrument approach procedure.
d) After the aeroplane has left the track of the initial instrument approach, the flight phase outbound from the runway should be limited to an appropriate distance, which is required to align the aeroplane onto the final approach. Such manoeuvres should be conducted to enable the aeroplane:
i. to attain a controlled and stable descent path to the intended landing runway; and
ii. remain within the circling area and in such way that visual contact with the runway of intended landing or runway environment is maintained at all times.
e) Flight manoeuvres should be carried out at an altitude/height that is not less than the circling MDA/H.
f) Descent below MDA/H should not be initiated until the threshold of the runway to be used has been appropriately identified. The aeroplane should be in a position to continue with a normal rate of descent and land within the touchdown zone.
4) Instrument approach followed by a visual manoeuvring (circling) with prescribed track.
a) The aeroplane should remain on the initial instrument approach procedure until one of the following is reached:
i. the prescribed divergence point to commence circling on the prescribed track; or
ii. the MAPt.
b. The aeroplane should be established on the instrument approach track determined by the radio navigation aids, GNSS, or ILS, MLS, GLS, or PAR in level flight at or above the MDA/H at or by the circling manoeuvre divergence point.
c. If the divergence point is reached before the required visual reference is acquired, a missed approach should be initiated not later than the MAPt and completed in accordance with the initial instrument approach procedure.
d. When commencing the prescribed circling manoeuvre at the published divergence point, the subsequent manoeuvres should be conducted to comply with the published routing and published heights/altitudes.
e. Unless otherwise specified, once the aeroplane is established on the prescribed track(s), the published visual reference does not need to be maintained unless:
i. required by the State of the aerodrome; or
ii. the circling MAPt (if published) is reached.
f. If the prescribed circling manoeuvre has a published MAPt and the required visual reference has not been obtained by that point, a missed approach should be executed in accordance with 5.b. and 5.c.
g. Subsequent further descent below MDA/H should only commence when the required visual reference has been obtained.
h. Unless otherwise specified in the procedure, final descent should not be commenced from MDA/H until the threshold of the intended landing runway has been identified and the aeroplane is in a position to continue with a normal rate of descent to land within the touchdown zone.
Originally Posted by
Giannipilota
Il problema è proprio che sappiamo già che riattaccheremo, 2400 metri non sono sufficienti e il mio intento è far giungere alle 3 Authority questo messaggio.
Non puoi sapere che dovrai riattaccare, se arrivi alle minime e la visibilità è sufficiente, inizi il circling, altrimenti riattacchi. Se ad ogni punto del circling perdi i riferimenti richiesti, riattacchi. La visibilità richiesta è per iniziare l'avvicinamento, poi procedi con le condizioni che trovi in seguito, che potrebbero essere peggiori o migliori.
Il mio aereo è un C, ma faccio il circling a 130/135 nodi, ben differente dai 180 che vengono sempre citati.