Ask The Pilot

[tuppaware]

Sounds like an oil breather pipe. I'll have a look next time I get a chance.

Yeah I noticed how much smoke comes out on one of those after landing into LAX.. I thought they were part of the change post-explosion

 

[NM]

Yeah I noticed how much smoke comes out on one of those after landing into LAX.. I thought they were part of the change post-explosion

Don't believe there was any such mod post the QF32 incident. I noticed it first time well before that incident. Was just reminded of it again on Saturday when taxing and waiting on the ground at SIN.

 

[Flying Fox]

OK please don't laugh too hard.. I was thinking about mid-air refueling for commercial aircraft.

Would it be possible for a small fleet of aircraft (in QF's case) to be modified for mid-air refueling to perform the SYD-DFW and AUS-LHR routes non-stop?

I was thinking that the aircraft could take off and then once airborne refuel mid-air early on in the flight and then cruise all the way to their final destination without a 'splash & go'.

Why don't commercial aircraft do this?

 

[markis10]

I was thinking that the aircraft could take off and then once airborne refuel mid-air early on in the flight and then cruise all the way to their final destination without a 'splash & go'.

Why don't commercial aircraft do this?

I would imagine the cost is the issue, you are probably adding around 4-6 hours of operating costs equivalent to the aircraft you are refueling to each flight, when a technical refueling stop might add an hour and a lot less risk associated to it.

 

[jb747]

OK please don't laugh too hard.. I was thinking about mid-air refueling for commercial aircraft.

Would it be possible for a small fleet of aircraft (in QF's case) to be modified for mid-air refueling to perform the SYD-DFW and AUS-LHR routes non-stop?

I was thinking that the aircraft could take off and then once airborne refuel mid-air early on in the flight and then cruise all the way to their final destination without a 'splash & go'.

Why don't commercial aircraft do this?

For a start you'll have the cost of tanker aircraft. Then the cost of modifying the receiver aircraft. Then you have to train the crew. Then you'll have to keep them current.

Anyway, it's dangerous and quite difficult. Much safer, easier, cheaper, to just make a tech call.

 

[Flying Fox]

Anyway, it's dangerous and quite difficult. Much safer, easier, cheaper, to just make a tech call.

Whilst I realise its probably dangerous having planes so close to each other, I didn't realise how difficult it was. I guess the documentaries that I have seen demonstrate it as quite routene.

 

[awilcockson]

I didn't realise how difficult it was. I guess the documentaries that I have seen demonstrate it as quite routene.

Look for a Canadian TV series called Jetstream. It follows a group of pilots going through the F-18 conversion course. I think episode 3 covers air to air refueling. It most definitely does not look easy

 

[Sifor]

Mid air refueling is incredibly difficult. There are two types, 1. hose and drogue (or "basket") and 2. boom. You need to have a closing speed of about 3-5kts so that you don't miss or damage the basket, or the probe on the receiving aircraft. When you approach the basket it starts to jump around due to the turbulent air from the receiving aircraft's nose. See a picture here: Basket

It becomes even more difficult when the receiving aircraft only takes a boom since you then need to have a dedicated person ("boomer") located below the tanker's tail to insert the boom into the receiving aircraft's receptacle. Both tanker and receiving aircraft must maintain their speed and altitude since the probe is not as flexible as the basket is (which is connected to a hose, so it allows a little movement). See a picture here: Boom and operator

Myself and another mate of mine from RAAF YAMB take turns in flying the A330 MRTT tanker and Super Hornet in Flight Sim X (FSX). While FSX doesn't replicate the bouncing basket it does a bloody good job at making it generally difficult. The smallest inputs are required otherwise the receiving aircraft starts to bounce up and down as you try and correct the mistake of being heavy handed.

The economics as others above have said would make civilian air refueling impractical. The cost of putting up a tanker would outweigh the inconvenience of landing and safely refueling.

With regards to the video below, I can't imagine I'd feel safe with static discharges and fuel mixing.. It's probably safe given that once the two aircraft join the charges are equalized but still... if for some malfunction fuel starts to flow before coupling.. big boom!

[video=youtube;KVzpV3V_V3U]http://www.youtube.com/watch?v=KVzpV3V_V3U[/video]

 

[samh004]

With regards to the video below, I can't imagine I'd feel safe with static discharges and fuel mixing.. It's probably safe given that once the two aircraft join the charges are equalized but still... if for some malfunction fuel starts to flow before coupling big boom!

[video=youtube;KVzpV3V_V3U]http://www.youtube.com/watch?v=KVzpV3V_V3U[/video]

At least that video shows that big aircraft can participate. Really cool view from there!

 

[Sifor]

Pretty much any aircraft (including helicopters) can be refueled in mid air providing they have the necessary equipment. However, a problem with large aircraft is that a wind buffer (like driving past a big truck) is generated between the tanker and receiving aircraft which can cause handling issues..

 

[Flying Fox]

Thanks all for your input and not laughing too hard.

Great video too. The 'target' aircraft looks like a B747 so I'm assuming its Airforce One but the paint job doesn't look right. Can anyone clarify?

 

[awilcockson]

Great video too. The 'target' aircraft looks like a B747 so I'm assuming its Airforce One but the paint job doesn't look right. Can anyone clarify?

It's a USAF E-4. Which means it might have been Air Force One at the time, but I'd say not based on the paint job.

 

[simongr]

With regards to the video below, I can't imagine I'd feel safe with static discharges and fuel mixing.. It's probably safe given that once the two aircraft join the charges are equalized but still... if for some malfunction fuel starts to flow before coupling.. big boom!

Have there been any instances of big booms from mid air refuelling though?

 

[Sifor]

Have there been any instances of big booms from mid air refuelling though?

No there have not been any "big booms" to my knowledge, since fuel only flows when correctly coupled with the receiving aircraft. That doesn't mean I'd like to test it in the presence of static electricity...

 

[jb747]

Now, back up a little. How many of you, who have replied, have actually done it? Didn't think so.....

The simple fact that is so far from being cost effective, that it would never be done...

Formation flying. You'll have to teach everyone who might participate how to do it. Have a think about it. How do you handle a rejoin...at night....or in cloud ('cos the weather will never conveniently move so that you can tank). The aviation world spends its time keeping aircraft apart, and here you want two within about 30 feet of each other. You'll note that all of the aircraft involved belong to air forces...in particular, one air force.

Insurance. Ha.

The turbulence from the lead aircraft is a huge issue.

Yes, it can be done by big aircraft. But, it's actually done by a very small group of people, who basically do it every working day. And even then they come together every now and then. A much more cost effective, and way safer, solution is to simply charge more, and carry less people.

 

[simongr]

Now, back up a little. How many of you, who have replied, have actually done it? Didn't think so.....

The simple fact that is so far from being cost effective, that it would never be done...

I totally agree - I was just intrigued by the risk assessment element - empirical evidence suggests that although it is not without risk it is also something which has fewer accidents than normal flying. Anyway soon we will be moving to hypersonic jets and it will only be a 2 hour flight LHR-SYD

 

[jb747]

I totally agree - I was just intrigued by the risk assessment element - empirical evidence suggests that although it is not without risk it is also something which has fewer accidents than normal flying. Anyway soon we will be moving to hypersonic jets and it will only be a 2 hour flight LHR-SYD

How do you work out that it has fewer accidents than normal flying?

Hypersonic...you must have been believing Airbus media spin. In 2050...I expect they'll be flying the A320, 330, 350, 380 and variants thereof. They'll have a new poster out for the 2070 model...

 

[markis10]

It's a USAF E-4. Which means it might have been Air Force One at the time, but I'd say not based on the paint job.

Paint Jobs have got nothing to do with it being Air Force One, as thats the callsign used for whatever aircraft is carrying the president, the normal Presidential aircraft is a VC25, not an E4 or nightwatch aircraft which will normally be in close location to the VC25 on a tour. Two E4s visited Australia, one was in CBR while the other in BNE when President Bush was here in 2008.

 

[oz_mark]

How do you work out that it has fewer accidents than normal flying?

Hypersonic...you must have been believing Airbus media spin. In 2050...I expect they'll be flying the A320, 330, 350, 380 and variants thereof. They'll have a new poster out for the 2070 model...

Fuel surcharges in 2050 might be quite something though!

 

[markis10]

At least that video shows that big aircraft can participate. Really cool view from there!

This video gives you an idea of how hard it would be to do it from a civil heavy, its a tanker being refueled by a tanker.

YouTube - ‪Tanker Refueling Tanker‬‏


The optical guidance systems are clearly displayed in a photo taken of the new MRTT arriving into AMB by Craig Murray over at Jetspotter

http://www.jetspotter.com/forum/phpBB3/viewtopic.php?f=1&t=10691&start=60

You can see one of the RAAFs tankers at BNE being built.