the UK LTN-BJL-HLE service has to be loaded to make money -- will the TUI a/c be limited on payload (usually 189 Y) but I see she is in a lower density 2 class W/Y fit and do they sell (or will have rights to sell) the LTN-BJL sector in which case some pax will disembark at BJL anyway - I dont see fares for BJL though. Would they be carrying island reserve as the alternates are a long way from St Helena? |
If they could make it work fuel and economy wise with a Classic from a driver's perspective it would be a lot easier as the classics have far more benign handling qualities in gusty conditions than the NG.
Reading between the lines, it sounds like the Comair crew who went in there (who I imagine were probably senior TREs/Performance pilots) weren't massively comfortable and probably want to develop a better knowledge base and a serious training program before making a decision either way. I am sure it will be a Cat C airport requiring special crew training anyway and they currently have a limited knowledge base. Perversely, a heavier aircraft might make things easier for the crew than an empty one - below 60t the 738 gets significantly less stable in gusty conditions. Test flights in a Hercules would not necessarily have told you much as conditions a prop driven transport might find perfectly manageable could be a no go in a swept wing jet. |
the Comair crew operating last weeks flights are interviewed on the YouTube clips by the local news hack guy - quite interesting to watch and see their comments about the winds etc https://www.youtube.com/watch?v=vndwvM6ieTw move onto 4m.20s
He did not hint at all then they have now to go back to the table to re-look at the data etc the crew were the CP and senior operating officer etc etc the guy who did the landing was the chap who had done all the planning |
Please look at the necessary requirements regarding nav fit-out, fire suppression etc before posting. Some of your remarks are unprofessional.
If you try to load the "Island Resv" you will probably find yourself overweight for FHSH and its short runway. If you consult your lap top, FPPM, FCOM in that order you are well placed to comment. If you haven't or can't then take care not to say anything foolish. Ju Now, going on from there let us say that a landing weight of 57 tonnes applies, there are no defects everything is tickety boo. Landing Distance (LFL*0.6) 3030 feet by my laptop Landing Ground Roll 1670 feet ditto Is that not average deceleration of 15.5 ft/sec/sec? You check it for me. FAOR FHSH TO FUEL 14300kg: Zero Wind ISA Conditions: FIELD AND WT LIMITED Payload 11000kg pax and bags Flt Time 280mins Air Dist 2029 am [zero wind ISA remember] RoC 1520fpm RoD 1470fpm Mach No 0.783 nominal Nett AS 434kts Nett GS 434kts FUEL 14300kg OEW 42200kg ZFW 53200kg TOW 67500kg DIV/ISLD 1600 kg 2400 kg/hr 40.0 min 320.0nm HOLD 1600 kg 2400 kg/hr 40.0 min CONT 620 kg inc start and taxi TOTRES 3820 kg so it cannot be Island Resv but a "re-dispatch" LDG 57020kg Now go back and check and you will see that at 60 tonnes all up you might have to go back to Windhoek! I was going to add more but it would not fit this page. No matter. But you have to be diligent. You have to do your sums and if the answer does not pan out then what you are proposing is not operationally possible I hope this has helped and is not too simplistic. Thank you. |
the comair guys hinted landing on RWY 02 is calmer but which has no localiser and will always have a tailwind comp.
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The lack of a localiser isn't a huge issue as far as I can see as the RNAV approach is straight in and has usable minima.
As far as I can see, the issue are entirely performance and handling related with the Orographic turbulence and Windshear and prevailing winds. A quick play with the Boeing OPT suggests with a 10kt tailwind and an OAT of 25° (20kt quartering tailwind with 17kt SW) and no reverser credit at 57t Max Autobrake has you stopped in 1338m so you have a good few hundred meters for mum in terms of runway length. I am only going by tables for dispatch landing weight but surely you could legally dispatch assuming the into wind runway allowing a higher dispatch landing weight then use the inflight performance onto the opposite runway if conditions are too rough? With a 5kt headwind you could dispatch up to 60t MLW. All getting a bit performance geeky but ultimately as long as the flight ops guys think the operation is safe in the prevailing conditions, I can't see too many performance issues. |
so you have a good few hundred meters for mum in terms of runway length.
And to ensure you have a solid escape route = div altn for mum as well. People talk about the B734 being better than B738. There is also the B737NG. In the environment where I operated all three I can't remember having any significant landing difficulties. NG slippery in descent, yes. However, there was a significant difference in engine & wing performance between classic & NG in terms of payload & range. That might have more affect on such a route than the rock & roll of the last 500'. |
Where would they use as an alternate? Windhoek is 1,367 nm on the GC from St Helena.
And to ensure you have a solid escape route = div altn for mum as well. People talk about the B734 being better than B738. There is also the B737NG. In the environment where I operated all three I can't remember having any significant landing difficulties. NG slippery in descent, yes. However, there was a significant difference in engine & wing performance between classic & NG in terms of payload & range. That might have more affect on such a route than the rock & roll of the last 500'. |
Alternate
To answer your question fireflybob, to the best of my knowledge the US authorities have agreed to allow Ascension to be used for diversions and 1 scheduled flight every 2 weeks. Wideawake airfield is about 700 nmi away GC.
I really hope that procedures or systems can be found to get round the problem with the orthographic winds. Does anyone know of other airfields besides Madeira where these kind of problems have to be overcome? |
Will the Comair flights be bookable with connections to and from London on BA.
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St Helena airport opening postponed - again | News | The Independent
The Independent also reporting the postponement of the Atlantic Star service from Luton as well as the Royal opening ceremony |
cape town?
i do not know why CPT has not been mooted for a scheduled service as tourism and wealth there would attract many people to do a trip over to the island.
or is CPT next on the list? |
Cape Town is actually slightly further than Johanesburg to St Helena plus it offers far more connections than Cape Town.
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I really hope that procedures or systems can be found to get round the problem with the orthographic winds.
Do you mean 'orographic' winds? What kind of 'procedures' & 'systems' to you have in mind beyond piloting skills? Regarding airfields with wind problems = most of the Greek islands, Gibraltar, LTN on a nasty 1/4 wind gusty day; NCE, GRO, GEN, Santander, and many others. They may not all be orographic wind problems, some will be rotor from local hills. Even katabatic effects at night. Many of the sea-side airfields squeezed in between hills and the beach will give problems. |
Johannesburg to St Helena is 1987 nm.
Cape Town to St Helena is 1701 nm. Even Cape Town to St Helena via Walvis Bay is 1912nm, following the coast before heading out. Distances using Jeppe. Cape Town route is preferred by the majority of Saints, and there are sufficient onward connections from there. |
Originally Posted by very old flyer
(Post 9361614)
Johannesburg to St Helena is 1987 nm.
Cape Town to St Helena is 1701 nm. Even Cape Town to St Helena via Walvis Bay is 1912nm, following the coast before heading out. Distances using Jeppe. Cape Town route is preferred by the majority of Saints, and there are sufficient onward connections from there. (BA LH KL TK EK QR MH SQ AB DE MT) CPT-HLE is about 3100 kms JNB-HLE is about 3660 kms the new BA 738 could op JNB-CPT-HLE-CPT-JNB surely a benefit to all concerned - the FD crew needed for HLE special clearance ops gets on in CPT i dont get why this hasn't been done from the start |
i always thought that CPT was more desirable for the locals and tourists who can combine a 2 centre holiday with the Cape plus decent onwards connections to Europe with BA and KL and more high-seasonal ones from CPT (BA LH KL TK EK QR MH SQ AB DE MT) CPT-HLE is about 3100 kms JNB-HLE is about 3660 kms the new BA 738 could op JNB-CPT-HLE-CPT-JNB surely a benefit to all concerned - the FD crew needed for HLE special clearance ops gets on in CPT i dont get why this hasn't been done from the start The most important early connections from London are 'high risk connections with a transit time of only 1,5 h. BA 55 from time to time arrives late 3, 5 or even 12 hours. But now everything is up in the air anyway. It seems Comair is not keen any longer to fly to HLE, the 737-800 a 'slippery' plane under the wind conditions on the island. There are reports the Government is already looking for alternatives. And I don't see how ASSI could give a green light if airlines have such serious concerns. Back to the drawing board ! |
the 737-800 a 'slippery' plane under the wind conditions on the island. Regarding airfields with wind problems = most of the Greek islands, Gibraltar, LTN on a nasty 1/4 wind gusty day; NCE, GRO, GEN, Santander, and many others. They may not all be orographic wind problems, some will be rotor from local hills. Even katabatic effects at night. Many of the sea-side airfields squeezed in between hills and the beach will give problems. |
any s/h 757's in good nick knocking around?
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