red750 Posted July 9, 2018 Posted July 9, 2018 Why planes can only land at two Australian airports in thick fog
Birdseye Posted July 9, 2018 Posted July 9, 2018 The issue they don't mention in regard to Perth, is that in addition to cost, there is an absence of any suitable alternate airport for international carriers in Western Australia. If fog is in the forecast it can be very limiting as they have to carry significant additional fuel to either fly to the Eastern states, or to be able to return to destination. Before anyone mentions it, Learmonth and Kalgoorlie are not suitable alternates as they lack international aviation requirements.
facthunter Posted July 9, 2018 Posted July 9, 2018 Perth is indeed a concern for the reasons you state. The lack of Customs facilities (Over seas flights) would not stop you using those other places in an emergency but you can't PLAN on doing it. Europe and Asia have many close airports if one place goes out for any reason. It's best to divert before descending if you are going to have to as the climb back to the Best cruise level uses lots of fuel. Perth might as well be an Island the way it leaves you with nowhere to go. Nev
Birdseye Posted July 9, 2018 Posted July 9, 2018 Hence why I said "suitable alternate airport". Until they stopped operating into Perth, British Airways did actually flight plan out of WSSS with 'island reserves'.
facthunter Posted July 10, 2018 Posted July 10, 2018 A suitable bit of fiddling.... Island reserve is usually 2 hours at holding rate. Not much real use if Perth goes bad.. Nev
rep003 Posted July 10, 2018 Posted July 10, 2018 The lack of alternate for Perth may be the best argument for the expansion of Busselton to International standards .
facthunter Posted July 10, 2018 Posted July 10, 2018 Kalgoorlie, Meekatharra and Port Hedland are about all I know of.. Mt ISA is an alternate for Alice springs, but not a very suitable one in my view. (love your Avatar) rep. Nev
peter51 Posted July 14, 2018 Posted July 14, 2018 I can help with this one. I am a 737 Captain with QANTAS. Firstly the ground installation must support low vis ops. This requires mandatory standards of ILS, ground lighting and transmissometers. Transmissometers are devices that operate in pairs to measure lateral visibility accurately at the threshold, mid, and end segments of the runway. Generally only airports with high end ILS systems have these as they are required to support the low vis ops - now installed in Perth only recently. The ground systems are categorised from CAT 1 through to CAT IIIIb. Perth has recently been upgraded to CAT IIIb standards and supports Autoland with no minima and 75m visibility. Crew and aircraft have to be certified to make such approaches.The aircraft must still carry fuel for an alternate with fog and all its systems that support autoland must be serviceable - as must the ground systems. See the chart below. The various minma and required visibility are tabulated at the bottom of this chart. To utilise the lower minima the crews have to be highly trained over several Simulator sessions and given recurrent training and testing regularly every 6 months. CASA and other authorities dictate all the training requirements. Some operators may not have authority to use the lowest minima and some overseas low cost carriers may have only been given the minimum training - when you buy a ticket these days you really do get what you pay for. Of course they will say they are just as well trained as anyone else. We can use the 737 as an example. It only has a 2 axis autopilot - no rudder control on rollout - Boeing has only certified it to Autoland in CATII conditions. However QANTAS 737 aircraft have additional capabilty to land in worse conditions than CAT II - a Head Up Display which allows manually flown approach and landing to CAT IIIa minima. That means you need to see a few approach/threshold lights through the HUD at 50 feet above the ground before deciding to manually flare via flare cue in the HUD. More modern aircraft like the A330 have all the bells and whistles and can Autoland at the lowest minma CatIIIb. The pilot does not have to see anything at the minima callout to continue the Autoland in this case - however it is against the law to continue an approach below 1000 feet if the transmissometers are continuously reporting visibility below that published on the chart - unless you are out of fuel and options. So if ANY operating transmissomers were reporting below 75m then by law you would need to divert. So if you are travelling to destinations with a CATIIIa or b installation that suffer from fog in Australia - book on an Airbus i.e.Perth. However if the ILS ground installation is a standard ILS setup but has a Special Authorisation minmin E.G. Canberra, then go on a QANTAS 737 as we can go lower than all the other operators using our HUD. If you have any other questions Id be happy to answer. [ATTACH]36712[/ATTACH]
Birdseye Posted July 15, 2018 Posted July 15, 2018 It seems not much has changed then since my CATIIIb landing in the jump seat of a HS Trident during the late 70s.
Bennyboy320 Posted July 15, 2018 Posted July 15, 2018 The landing & rollout no dramas, it’s getting off the r/w & taxiing that’s more challenging & gets the heart beat racing.
Birdseye Posted July 15, 2018 Posted July 15, 2018 From memory, the Trident had a minimum RVR requirement of 75 or 100 metres. That wasn't for landing, but to give them a chance to follow the taxiway centreline lights. At Heathrow, ATC used to practice guiding the crash crews around using the ground radar (ASMI), just in case they were needed. Drivers wore an obscured helmet visor.
Bennyboy320 Posted July 15, 2018 Posted July 15, 2018 [ATTACH]36713[/ATTACH] These days with ground radar it’s a bit easier compared to the 1960’s. We only use CAT 3B, with CAT 3C it’s basically 0/0.
Birdseye Posted July 15, 2018 Posted July 15, 2018 They could always send out a tug to tow you in for 3C. Incidentally, regarding 'these days' note that the Heathrow Decca ground radar first came into use in 1967. Combined with the switchable taxiway centreline and stop bar lighting it was quite revolutionary.
peter51 Posted July 15, 2018 Posted July 15, 2018 Whilst it all sounds complicated and difficult - I can assure you that it is pretty easy and straight forward. Even single engine landings in 100m vis manually flown via the HUD is not too difficult after a bit of practice. Bit off topic but - There are dozens of more difficult manoeuvres carried out by GA drivers in the bush, Aeromedical helo crews picking up the pieces of accidents, military helo pilots inserting SAS boys or picking up our wounded in some god forsaken spot in Afghanistan etc etc. We shouldnt forget all those others flying tough missions in much more exacting and dangerous missions out there in the real world.
facthunter Posted July 16, 2018 Posted July 16, 2018 For all this stuff you get a a lot of training and checking. Autopilot (coupled) approaches are required. and the ground and airborne equipment fitted is functioning correctly. Monitoring of the process is big part of it. You don't just press a button and sit there like a stuffed dummy.. (I hope). Nev.
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now