Originally Posted by
rog747
Surely the 164m Runway Extension, and any other previously limiting Airfield parameters are already now sufficient and safe for EasyJet to operate their A320's on the planned summer series of flights to Palma, Faro, and Alicante without any undue Payload limits?
I was going to ask TCAS FAN the same Q as asked above by Sharklet_321
''What implications, if any, does this (The Tree Felling) have on the RWY 20 performance issues ?''
So,
my Q to TCAS FAN is:
Would this tree work be a factor in improvements to possibly permit loaded 737-800/737M-8 operations in the future?
We know the runway length and the width are OK for the Type, but the limits for such 737 Ops at SOU currently are, I believe, the Approach and Obstacle/clearway issues for arrivals and departures on RWY 20.
Is that so?
Thanks in advance....
Firstly I am somewhat flattered that you have confidence in my technical expertise. While I am not qualified to provide a definitive answer in respect of take-off performance I will attempt to provide some insight into the current performance limiting obstacle situation.
In respect of obstacles that impact RWY 20 approaches, from what I recollect, surprisingly the large rail shed south of Campbell Road, not the one north of it, limits the OCH and also requires displacement of the RWY 20 threshold. If this were to be removed it is probable that the OCH could be lowered by a minimal amount (few feet) but reduction of the distance that RWY 20 is displaced could be possible to increase the 20 LDA. This would require modifying the approach lighting, moving the PAPI and ILS GP, which together may make it not financially viable for any increased LDA realised.
ILS CAT 2 on RWY 20 would require removal of the previously mentioned shed, removal of the railyard south of Campbell Road, together with possibly reduction of height of the rail shed north of Campbell Road and extension of the approach lighting. All considered, CAT 2 probably not a financially viable option for the reduction of OCH by about 100 FT.
The minimum extension of the approach lighting system required would be 720 metres which would take it past the rail shed north of Campbell Road. So seriously doubt that this is ever going to happen.
More relevant for bad weather ops, ie fog, is the current RVR minima for an ILS approach. Best case for the CAT I ILS that SOU has would be RVR 550 metres. This only attainable if 720 metres or greater approach lighting is available. With the current 434 metres of lighting and the current OCH a RVR minima of 700 metres is possible.
What SOU can provide for approach minima, while not ideal, is obviously acceptable to operators who are naturally aware of an increased risk of diversion if fog prevails. They have been very lucky this winter.
SOU has the advantage of a standby CAT III airport just down the road which can normally accommodate diversions, and it doesn’t cost them a penny for this facility!!!!
You mention “loaded” in respect of 737-800/737M-8, by this I assume you mean fully loaded, ie max take-off mass (MTOM), the answer is no. A fully laden B737-800 requires around 2300 metres TORA, whereas an A320neo requires around 1951 metres.
Similar to SEN, SOU is never going to accommodate either aircraft at MTOM, but can still provide enough TORA/TODA to accommodate many economically viable routes at take-off eights less than MTOM.
The Marhill Copse trees still often have an impact on take-off performance. The runway extension has improved this by being able to start the take-off roll 164 metres further north away from it. I however suspect that there is still an impact, albeit less than the pre-extension runway.
In order to optimise take-off weights, as mentioned in an earlier post of mine, the icing on the cake would be the extension plus reduction of many trees in Marhill Copse.
Its now a waiting game to see what, if any, impact on take-off performance the removal of the 14 trees reported by SouthernAlliance will have, if it goes ahead. Assuming the felling takes place imminently, as mentioned in my post #2839, its going to mid/late summer before a new Type A chart is published. Until this happens aircraft operators cannot quantify the impact on take-off weights.