Ask The Pilot

[jb747]

Re: Perth alternates

I've thought about this one a bit & am dying to know what the answer was - only close alternate that I can think of would be Ohakea AFB - I dont know for sure but suspect the Regional airport at Palmerston North wouldn't have a runway long enough, and others would be too far away. Possibly Ohakea is too far in 'dirty' configuration too?

I can't think of any other solution other than ignoring the normal approach/ landing requirements based on experience - depending on wind conditions into wellington that could also not be an option though... the curiosity is killing me!!

You cannot divert. There are no options for that at all.

The problem is that you can't land at Vref20+20. Can you fly the approach at a slower speed? How slow would you need to be able to land safely? The approach speeds, even in this sort of case have some sort of margin (call it 20%) back to the stall. The effect will be a higher pitch attitude, and greater tail strike risk.

Can you make the runway longer? Not really, but you can make a bit more available by aiming a little shorter. How about targeting 700' instead of 1,200' from the start of the runway. You don't aim at the end...unless there is no choice.

So, a couple of options. A bit of each and the numbers look much better.

 

[Dale Eastham]

Re: Perth alternates

Thanks JB, much appreciated.

 

[jb747]

Re: Perth alternates

Just sorting some images for another forum, so I thought you might enjoy a look at a previous life.



and the really fun jet...

 

[Franky]

Re: Perth alternates

and you will recall jb747, that we gave the fun jets to the Kiwis for a song..

 

[straitman]

Re: Perth alternates

and you will recall jb747, that we gave the fun jets to the Kiwis for a song..

.... and then leased them back:!:

 

[jb747]

Re: Perth alternates

Believe it or not, they actually live on, flying for an aggressor company in the USA. Draken.

 

[clazman]

EK fly Dubai - Melbourne - Auckland, do you know if this is a business decision or a need to refuel?

 

[jb747]

As they have a direct service between Dubai and Auckland...I think that tells you the answer.

 

[mushez]

EK fly Dubai - Melbourne - Auckland, do you know if this is a business decision or a need to refuel?

As JB has pointed out, business, as they could also fly direct and now do.

My understanding of the reasons - some maybe historic now - but still cemented the route from the start:

Parking Aircraft Costs & Accommodation Costs. Crew on a DXB-MEL flight require a 48 hour layover due to the long flight - so add a Tasman flight and it is a 24 hour layover - and cheaper to put them in a NZ hotel than AU hotel. EK like/wanted to arrive at 6am each day, and depart at 9pm each day, parking the aircraft somewhere for the 15 hours - and found with the costs, was cheaper to fly the Tasman and park it there for 4-5 hours and then fly it back - not incurring any parking costs within AU or NZ as I understand it. EK want the bulk of flights to AU departing DXB around 10am, with them arriving into DXB at 5am from AU - so people sync and transfer to other onwards bound flights into Europe with ease with their hub and spoke model they run - to achieve this, has 15 hours - or as in the case of EK404/EK405, is a 10 hour park in MEL because of the time consumed flying via SIN.

Airfreight - Airfreight on the Tasman was profitable for EK, that flying the Tasman daily just with freight made a profit before they put one PAX on board from the first day they flew the Tasman with 5th freedom rights.

 

[mjt57]

Re: Perth alternates

Just sorting some images for another forum, so I thought you might enjoy a look at a previous life.

Where's the one that you took of another A4 on a steep climb over Nowra? That was a rather spectacular shot.

 

[jb747]

Re: Perth alternates

Where's the one that you took of another A4 on a steep climb over Nowra? That was a rather spectacular shot.

On the way up...



and on the way down...




There's actually quite a few shots in the sequence, so I don't know exactly which ones are out there. Pity I didn't get the guys to drop the tanks off for the flight. You rarely saw the aircraft clean, especially the trainers.

 

[JohnM]

Re: Perth alternates

How much do those external tanks affect performance, jb?

On the way up...

View attachment 89431

and on the way down...

View attachment 89433


There's actually quite a few shots in the sequence, so I don't know exactly which ones are out there. Pity I didn't get the guys to drop the tanks off for the flight. You rarely saw the aircraft clean, especially the trainers.

 

[mjt57]

Re: Perth alternates

On the way up...

That's the one.

There's actually quite a few shots in the sequence, so I don't know exactly which ones are out there.

You emailed me a few of them, back in the aus.aviation days.

Pity I didn't get the guys to drop the tanks off for the flight. You rarely saw the aircraft clean, especially the trainers.

A lot of the display aircraft that you see at shows all seem to have their tanks on. Make them look ungainly, or that they're carrying some massive bombs...

 

[jb747]

Re: Perth alternates

Like everything in aviation, they were a trade off. In an actual war, you'd jettison them if you needed to. That was generally a no no in peacetime. We had two sizes of tanks. The ones in the pictures held 2,000lb of fuel each. There were smaller 1,000lb tanks that were only used at sea. The aircraft could carry up to three of the 2,000lb tanks. We rarely flew without at least one, even if it was empty. You could land (ashore) on a tank and do virtually no damage to the aircraft. This was tested a few times over the years.

When clean the aircraft was limited to 640 kias and mach 1.2. The tanks were limited to 575 kias and .9 mach. It was very easy to overspeed the single tank configuration (one on centreline)...you barely noticed it was there. Two tanks maxed out at about 575 knots. Some aircraft would exceed it if allowed, and some couldn't. Three tanks was a dog. Not only was it extremely heavy (at least on the scale I used in those days), but it was very draggy, with the drag from each tank interfering with the flow from the others. With the 3 tank configuration, you only got about 800lbs of range benefit from the centre tank.

There were two other tanks. The Kiwis had 4,000 lb centreline tanks. These were low drag, but with the same capacity as the pair we normally used. A great transit configuration. There was also the 'buddy store'. This was a combination drop tank, and air refuelling rig. Using that, the tanker could offload most of his fuel load to other aircraft. In the picture below, the tanker is carrying a buddy store on centreline, and the receiver aircraft has two tanks on the wings.

 

[petercr]

JB, great photos... Was reading Air Forces Monthly just before Xmas showing A4's in cammo providing dissimilar air combat and wondered if they were ex RAN... The article was about them being used in Germany so they possibly weren't? (referred to as A4N's)

 

[jb747]

JB, great photos... Was reading Air Forces Monthly just before Xmas showing A4's in cammo providing dissimilar air combat and wondered if they were ex RAN... The article was about them being used in Germany so they possibly weren't? (referred to as A4N's)

There are a couple of companies using A-4s (amongst other things) to provide training. The Ns are run by a Canadian company, and I think are ex Israeli.

Draken is a Florida based company that has the ex Kiwi A4Ks...and some of them were originally A4Gs. Draken International | Draken International

 

[defurax]

Re: Perth alternates

Ah, the myths about the amount of fuel aircraft carry.
....
When you get to places like Tahiti, which is the only decent runway within a long way, you cannot reasonably carry an alternate, so generally there's some form or remote fuel allowance. Basically something like 90 minutes of holding on top of anything else that might be required.
...

Hi JB, this is quite topical as I saw that AF76 from LAX to PPT (Tahiti) last Saturday flew towards PPT at 36,000' but then decided to go to RAR about 700 miles away due to bad weather (i.e torrential rain) (www.flightradar24.com/data/flights/af76/#c3ced8a). So my question is if you know that the weather might be horrible in such an isolated place, is it more practical to plan the flight as if the real destination was RAR to begin with or RAR is always a good alternative to PPT and this is business as usual? I'm just wondering if there is a threshold at which the likelihood of PPT being unavailable makes it more convenient to plan RAR as the final destination and add some extra fuel to allow for holding around RAR?

Of course I imagine another option is not to takeoff from LAX...

 

[Mrmaxwell]

Re: Perth alternates

I was recently landing into BKK (ex KUL) on MH788 when we had ATC put us in a hold for 2 or 3 loops. We then proceeded to land at which point I was looking out the window and could see Suvarnabhumi under us only thing was we were really high to be landing. At that moment the engines hit full throttle and we climbed up and proceeded a go around. The pilot came on and informed us ATC gave them the wrong vector due to runway change and they decided it wasn't safe to land and go around. My question - does this happen often and make sense? At point of our first landing attempt it was very obvious we were way too high...why wouldn't the pilots pick this up almost right away?

Flight path attached;

 

[jb747]

Re: Perth alternates

I was recently landing into BKK (ex KUL) on MH788 when we had ATC put us in a hold for 2 or 3 loops. We then proceeded to land at which point I was looking out the window and could see Suvarnabhumi under us only thing was we were really high to be landing......

What date?

 

[Mrmaxwell]

Re: Perth alternates

What date?

Jan 14, 2017.