North to Alaska

[Splitpin]

I've spent a good part of the afternoon on Youtube watching plane-spotting videos, courtesy of Aviation Videography.
As a freight dog enthusiast, Anchorage is heaven.
Definitely added it to my bucket list...in fact it's just been moved to the top.

I'm going to grab some stills and post them soon.

[Splitpin]

Took a while, but here you are....

[deaneb]

I have noticed on Flight Radar that Anchorage is a hotspot for 747 freighters from all around the world. From what I understand it allows for one of the shortest distances between Asia to USA, so they can carry more cargo (and less fuel), and then use Anchorage as a hub to fuel up.

[Splitpin]

Thanks for looking Mr D..arent those 74's great.

[Charl]

Yes nice to see those Big Birds.
Looking especially at the last shot, which must surely be turning in its own length:
I am wondering how that is controlled?
CP can no doubt cast light on this.
What's the tightest permissible turn?
How far are the outside engines powered up? Inside ones?
Do the MG bogeys steer? can't recall.

[cowpatz]

Without doubt the best aircraft ever produced.
As you know the 747 has 4 main bogeys. 2 wing gear and 2 body gear. It can land with any 2 pair combination ie. only body gear, only wing gear or one of each.
The body gear bogeys (trucks for Americans) are steerable. They move in the opposite direction to the nose wheel steering. Both the nose gear and body gear are powered by the number 1 hydraulic system.
When the nosewheel steering angle exceeds 20 degrees the body gear steering operates. It is activated when the groundspeed reduces through 15 kts. During takeoff as the speed increases through 20 kts the body gear is hydraulically centered and deactivated. If the gear is not centered or deactivated on take of then a takeoff config warning would activate requiring the TO to be rejected. From memory the 747 - 200 was manually activated/deactivated by an overhead switch operated by the flight engineer.
Pilots sit just under 30m forward of the body gear and 2m forward of the nose wheel.
Despite it's size the aircraft is very manoeuvrable. It can turn tighter than a 777 & 787.
Min runway width for a 180 degree turn:
747 = 46.6m
777-300 = 56.5m
787-9 = 47m

The turning technique required:

• Position wing gear as close to the runway edge as possible
• come to a stop
• Turn the steering tiller hard over
• Apply power to outboard engines whilst apply light opposite wheel brake
• maintain a speed of 5 to 10 kts

The hydraulics are so powerful that they would scrub the body gear into position at standstill. A big strain on the tyre sidewalls.
The 777 also has a main gear steering set up powered by the center hydraulic system. It only has wing gear which consists of a triple axle bggey set up with 6 wheels per bogey. Only the aft axle is steerable and activates when the nosewheel steering angle is greater than 13 degrees.

[Splitpin]

"Without doubt the best aircraft ever produced." I agree 100% CP ...Love them.
Thank you very much for the tech details as well, I love all that stuff as well

[SA227]

Anchorage is awesome.

Flew into there in a Biz Jet in 2012 and on finals for 15 at 0130 the tower controller asked where we were from? When I told him, the response was "been there, I use to be a lifeguard at Piha." And so started a long conversation in between looking after the Freight Dogs

[Charl]

747 = 46.6m

Well inside its own length, then!
Great little nuggets of information, thanks CP.