Tag Archives: lock

Follow the Lock Staff Instructions

The smaller of the locks at Ballard has mooring points that float with the water level so the boats can tie up and wait for the process to be over.  In the big lock, the boats have to let out or take in their lines as the level changes because they are tied to the lock side itself.  When the boats were down, the lock crew shouted out clear instructions to everyone to keep their lines tight until instructed to do otherwise.  As the boats had come in, we had watched with some amusement a guy who didn’t seem to know how to handle his boat.  Judging by the text on the boat, it was a share scheme of some sort.

I wandered away as they started to move out of the lock but Nancy and Mum stayed to watch.  Judging by the shouting that followed, one of the boats had let off his lines early.  When the gates open, there is a flow out of the lock which starts to take loose boats with it.  One of them started to rotate and take the other boats with it.  I missed the whole thing but I was able to guess who was the one that hadn’t followed instructions.  Hmm…

Some Small Pleasure Craft

Two small boats came through the locks while we were there.  One was just over 50m in length while the other was much smaller and just under 50m in length.  Both of these boats looked like they might be quite comfortable.  They were also both flagged in the Caribbean.  A quick Google search on each showed that they were available for charter.  Both seemed to have plenty of people on board but they looked like they might have been the crew rather than the guests as they seemed all business as they handled these tiny boats through the lock.  If I decide to get a boat at some point, I might be tempted by either of these.  I do prefer one over the other but I suppose I could make do with the less preferable one if the price were right.

The Commercial Craft Have Precedence

I learned something new about boat traffic while at the locks in Ballard.  There is a clear rule structure about which types of boats get precedence when traversing the locks.  Priority goes to government boats and emergency services.  Then scheduled commercial boats followed by unscheduled commercial boats before you start to get to the pleasure craft that make up a big chunk of the traffic.  One of the boats had tried to enter the lock and they got a loud verbal warning that they had jumped the traffic lights and that a commercial craft was going ahead of them.

After hearing this, I chatted with one of the lock staff and he explained the way in which things are prioritized.  The boat that first demonstrated this was a fishing vessel that went through the smaller lock and was a pretty snug fit (although the crew didn’t seem to even pause when running it in to the lock).  The other commercial vessel that came in was substantially larger.  It was directed to the main lock while the smaller traffic continued to use the smaller one.  Seeing such large vessels come through and the change in perspective from when they were below you as they entered to being so much higher when they left was quite impressive.

Kayak Club Outing

A few kayakers were out while we were in Ballard.  One group appeared to be either a club or a training course.  Most of them were in identical looking kayaks while they seemed to be escorted by a pair of kayakers in more professional looking rigs.  They did not go into the lock but came to check it out before heading back in the opposite direction.

Another pair came from the direction of Lake Union and were heading towards Puget Sound.  They did take a ride through the lock.  Since they did not have ropes to tie off during the lowering of the water, they hung on to one of the other boats as the water level was lowered before paddling out of the lock and on their way.  I imagine being at the bottom of the lock in a kayak is quite intimidating but they seemed like seasoned users.

Is Climbing Out Via This Ladder Making Things Worse?

The salt water end of the locks is tidal.  The walls clearly show how high the water will rise with a combination of algae and barnacles.  The barnacles seem to have got themselves well established everywhere.  There is a ladder built in to the wall to assist you if you end up in the water and need to get out.  However, judging by how many barnacles are now in residence on the rungs of the ladder, I am going to guess that climbing it will be a very painful experience.  Maybe there is a better way?

Redundant Capstan

There are three sets of lock gates on the main lock at Ballard.  If the two end sets are used, the full length of the lock is available.  However, if that isn’t needed, a middle set of gates can be used which reduces the amount of water displaced.  The gates are now moved by hydraulic rams.  That wasn’t always the case though.  Alongside each set of gates are some capstans.  Now preserved and serving only a decorative function, they are a reminder that things used to be a bit more manual.  The markings of the manufacturer are nicely maintained on the top of each capstan as a testament to companies long gone that used to make such engineering efforts.

Another go at the 777-300ER wheels

I have been trying to get evidence of a feature of the Boeing 777-300ER for many years. I previously posted on my efforts to get shots that showed the effect where the main gear bogie is locked to allow the aircraft to get a higher rotation angle at take-off. I have since had another go at this. Taking pictures during the winter has helped since the heat haze is a lot less obvious. Even so, the aircraft are usually quite a distance away. This time I managed to get a sequence that seems to show the effect quite well.

AU0E9767-EditI also had a go at doing the same thing from head on.  Not quite as clear cut but you can see some of what is happening.

AU0E5006-Edit

Boeing 777-300ER Main Gear

AU0E5067-EditWhen Boeing launched the 777-300ER, they took the stretched fuselage of the 777-300, a model that didn’t sell particularly well and married it to the updated wing that made use of the fuel capacity of the outboard portion of the wing that had been left when the original concept of a folding wing was contemplated.  The increased the weights of the jet, added far more powerful engines and, with the increased fuel capacity, came up with a winning formula that has done a very effective job of killing off the 747.

One problem that they had to deal with during development was runway length requirements for takeoff.  Even with the bigger engines, the long fuselage limited rotation angles at takeoff and meant a higher takeoff speed was required which meant a longer runway requirement.  Boeing came up with an interesting solution (after dumping some slightly more curious ideas).  The main gear on the 777 has a triple axle bogie.  Previously this had rotated about the pin attaching it to the main gear leg.  Boeing’s solution was to lock the bogie level during takeoff.

The result of this is to have the rotation of the jet at takeoff to take place around the rear wheels of the bogie rather than the gear leg pin.  The slight aft movement of the rotation point allows the aircraft to rotate slightly more nose up and gain a greater angle of attack.  This gives slightly more lift for a given speed.  This means an earlier takeoff and a shorter runway requirement.

I have tried many times to witness this at work.  First, it happens pretty quickly.  Second, I am often in a poor position to see the rotation point.  Recently I was at SFO to pick up some people.  I was getting a few shots prior to their flight arriving and a Singapore 777-300ER was taking off.  The rotation point is quite far away (although, if you are in the terminal, you might have a good view) and the heat haze is a problem.  However, I decided to get a sequence of shots anyway.  Now, how to use them.

Heat haze is crappy on stills but less of an issue with moving images so I decided to animate the sequence.  I imported all of the shots into Photoshop as layers in a single document via Lightroom.  The hardest part was aligning them.  I started at the bottom layer and then progressively made each layer above visible.  I then changed the latest top layer blend mode to difference.  This makes aligning them a lot easier since everything is black unless it is different.  I was focused on the gear so used that as the reference as the fuselage rotated.  Once each layer was in place, I changed the blend mode back to normal and moved to the next layer up.

Once they were all aligned, I used the animation timeline to make frames from each layer (and reversed the order since every time I do this they seem to be the wrong way around).  Then I could crop in to get the overall view I was after and save the file.  A Save for Web allows the generation of the animated GIF and we are done.  The image at the top is the final result.  It does allow you to see a bit of what is going on if you look closely although it is still a bit hard given the distance, the angle to the ground and the heat haze.  I guess I will have to find a location closer next time.