Side Scan of FG-1D Corsair debris field in Lake Washington

This image shows the location of the FG-1D Corsair in Lake Washington.  Located just off shore with access from shore for divers this site is primarily a debris field.  Most of the artifacts associated with this plane remain scattered throughout the debris field and while a popular dive site the notoriously poor visibility of Lake Washington has protected this wreck.

 

Corsair Dive 1/26/2011

Here's a couple of pictures from a dive to the Corsair in Lake Washington last week. Visiblity was average 5-6 feet or so. We noticed that someone has removed alot of the line from the wreck. There is now a jump in the line leading to the wreck, and most of the line that used to connect the pieces are all gone.                         

PV2 Harpoon - Lake Washington


PV2 Harpoon in Lake Washington - Another visit from Ben Griner on Vimeo.

We dive regularly on the planes in Lake Washington and this dive we ran more video to document the planes condition and any changes we see from year to year. This plane nosed directly into the mud and is stuck there vertically. The tail section is lying next to it in the muck with the bottom at approximately 145' fresh water.

Wreck of the PB4Y Privateer resting in Lake Washington


PB4Y Privateer resting in Lake Washington from Ben Griner on Vimeo.

Today was yet another great dive on this amazing wreck. Our goal today was to document the cockpit glass and two side turrets for comparison to previous video. This plane rests in 154' freshwater just off sandpoint.

For full HD click the video title and watch this video on vimeo.

Sidescan Imagery of Scorpion Site

The below images are of the site currently referred to as Scorpion due to is uncanny resemblance to a Scorpion.  This site is listed by NOAA as a plane but appears to be natural formation.  Two historically significant planes are within one mile of this site.  Images were taken with equipment from Scott Christopher and Sound Aquatics.  Resolution is limited with web publication.  Actual location was identified by Scott Boyd of Emerald Sea Photography.

Enhanced Side Scan Image from 150' Side Scan image from 75' 

PV2 Harpoon

Saturday, Marc Greenway, Laurynn Evans, and Scott Christopher set out on my boat to see one of the many relics resting on the bottom of Lake Washington. Greg Wilson generously volunteered to captain the boat for us and Ben Griner provided surface support. The weather on the surface was overcast, but the wind was light. This made the entry and exit to the water very easy. The plan was to spend 20-25 min on the plane and the about the same in deco to the surface. Greg dropped the line in a great spot. Visibility was SUPER for the lake, probably 15-20 feet, so there was no need to search for the plane as it was in plain sight upon descent. The great visibility allowed us to put into perspective the massive size and layout of this wreck. For those of you who don’t know the Harpoon sits nose down in the silt. The bottom is 140 ft and the top of the plane is at 118 ft. The tail section has fell off to the side, but with the great viz we had on Saturday we were able to see the entire plane. The cold fresh water oh Lake Washington as preserved this plane very well. We spent 22 minutes on the bottom exploring the plane from top to bottom. We then completed deco and surfaced to find that the overcast sky was replaced with sunshine. It was great to spend the day visiting this little piece of history and with friends. We spent a little time side scanning a new target. We found it on the depth sounder, but due to its location between a few large rocks, and resting on a very steep slope we had trouble getting an image on the side scan unit. We will try again this weekend. This is a large target, which that looks promising. Thanks to Laurynn, Marc, and Greg for a great day on the Lake

Video Survey Dive of the PB4Y Privateer in Lake Washington

Today our team dove on the wreck of the PB4Y Privateer resting in 150’ in Lake Washington. Scott Christopher and Geof Corriveau dove locating the plane and tying in. Upon finding the wreck they shot a small surface marker and Ben Griner and Greg Wilson dropped on the wreck behind them.

PB4YCockpitGlass.gifEach team spent twenty minutes on the plane followed by a 50% O2 decompression. Both teams used Ratio Decompression calculations independently calculating their own deco schedules based on actual average depths and run times. Viability on this dive was approximately 7-10’ and surface conditions were sunny and calm. In all it was a great day to be on the water. Marc Greenway and Shaun Gardner had the duty of captain and surface support today.

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Outside and inside cockpit

This plane is in excellent condition despite failed recovery attempts by the navy following it being ditched. Four of its anti-aircraft guns are still in place and three of the four engines remain.

Side scan imagery of the PB4Y Privateer in Lake Washington

Below is an image of the PB4Y Privateer resting in 154 feet freshwater in Lake Washington. This plane is notoriously hard to get a strong or clean image on side scan. In this image you can see the planes profile with enough detail to see the step up for the cockpit as well as the shadow of the planes elevated wing. The bump you see on the planes top over the wing is actually a reflection of an engine housing on the far wing.

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The side scan actually picked up the hand reel we left hanging on the drop line following a recent dive here.  We try to place our drop line in this general location on every dive as the planes wings do not show on the depth sounder.  This placement ensures we protect the sensitive wings from the lead shot.

 

 

 

The second image is looking down on the plane. Again due to the planes poor sonar signal the edge detail is not strong but the plane is clearly detailed.

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Video Survey Dive of the PV-2 Harpoon in Lake Washington

Scott Christopher, Geof Corriveau, Greg Wilson and Ben Griner dove the wreck of the PV-2 Harpoon in Lake Washington today. This plane crashed nose down and embedded its nose in the mud leaving the plane positioned vertically in the water. This plane also has its anti aircraft guns intact. The tail section of the plan has fallen to the side. There is some question as to when and how this occurred. Some speculate it was ripped off by people attempting to hook the wreck for fishing or diving but another possibility is that a large amount of air was trapped in the tail section. This theory could support why the plane sank perfectly nose down and eventually the pressure from the trapped gas was too much and broke the tail free.

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Greg Wilson approaching the top gun turrent

Scott and Geoff ran the search line and tied into the wreck with Greg and Ben following so that Ben could get as much video time as possible. This plane is virtually black underwater and its skin reflects little to no light. On this dive I swan the search line and saw the reel tied into the bomb rack and it took a minute to click that the wing should only be a few inches from me. Sure enough I had swum nearly have the length of the wing with it no more than 6-12 inches from my shoulder. This kind of thing can make diving in Lake Washington a little creepy.

Scott Christopher and Marc Pyle dive the Harpoon

This Saturday Scott Christopher and Marc Pyle dove the PV-2 Harpoon located Lake Washington.  The plane stands vertically in the water; the nose buried up to the cockpit resting at 140 feet and the tail section rising to 120 feet.  Marc Greenway acted as Captain for this team. The team spent 20 minutes on the bottom with approximately 7 minutes spent searching from the drop line.

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Cockpit windows resting at the mud line

On this dive the drop line was placed downhill and outside of the south wing. This wing tapers and at the tip is as much as 5’ off the bottom. The team passed under the wing a few times during the search without seeing it. Obviously visibility is still not great. Marc was shooting video on this dive with a new video camera and housing which seems to have worked flawlessly.

Side Scan Imagery of the Valiant

Below is the side scan pass of the Valiant in Lake Washington. The image is wavy due to rough surface conditions during the imaging. Of note are is the large log to the south (right) of the plane. Divers diving this site from shore often run into this log and then navigate back to the plane.Valiant.gif

This image was taken shooting up slope and hits the plane head-on giving a difficult picture.  We dove the site to verify the image was indeed the Valiant.

On-going exploration of the PV-2 Harpoon.

Over the summer of 2007 Puget Sound Divers successfully conducted more than 18 dives on the PV-2 Harpoon. Early in the summer visibility was quite good but starting in early fall and into winter has declined to a mere 1-2’. The bottom around this plane is very silty and with little to no current will stay suspended throughout the course of the dive. With this in mind and the inherent sensitivity of our planes we customarily drop a 4lb lead shot approximately 50’ from the plane. This requires a little navigation but with a slight sweep the plane is easy to find. The use of the light 4lb shot requires divers be okay with some scope in the line as boat wakes and a strong breeze can easily drag this across the bottom.

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Shaun Gardner has become quite good and navigating to this wreck and the last three dives I have done with him on this plane we have swam right to it. Our entire team has been on this plane several times now and I personally really enjoy this dive. It is relatively shallow at approximately 145’ and is easily explored with navigation time in 20 minutes. This type of dive affords an easy deco and often a second dive that day.

You will note on the side scan imagery the plane is nosed directly into the ground and stands straight up. The tail section has broken free and is lying beside the plane. There has been some recent controversy regarding the broken tail section as one of the early explorers of this site feels that this has been caused by people attempting to hook the plane. Missing this wreck is quite common due to its size but as stated above with a little practice is easily reachable with a simple drop line. If you are diving this wreck please do not anchor. The use of a drop line and a live boat is always a best practice when diving our wrecks.

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Click here for more information about the PV-2 Harpoon and about this drawing.

PB4Y downhill scan in Lake Washington showing a two large boulders west of the plane.

If you take a look at this sidescan image of the PB4Y you will see two large signatures off the nose of the plane. These are the infamous boulders that are occasionally dropped on by mistake. You can see that due to their size and close proximity to the plane that they could easily be mistaken on a depth sounder for the plane which typically has a poor signal due to its positioning.

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With this said, divers who are familiar with this site are able to swim from the rocks down to the plane.

PB4Y uphill scan in Lake Washington showing the hillside topography.

This scan was taken much like that of the 520 vessel #2 image. The side scan unit was placed very close to the bottom and turned up to allow the capture of as much of the hillside as possible. This image shows the shelf contour as it drops from 80’ to 200’.

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For those of you who enjoy scootering this wreck from shore these images should give you a good idea of your navigation. Our team often scooters this wreck as the shelf allows for a comfortable and natural decompression. We are using a 70’ single 50% bottle for this dive and ratio deco with our clock starting at 80’. This profile gives plenty of time on the wreck.

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If you have not been to this wreck by scooter please note that this plane is nearly a half mile from shore and there are gentle cross currents in this area.  Should you be forced to do an open water deco you will certainly be a long way from where you want to be. Measure your burn times ensuring your buddy can tow you home (or at least up the hill to deco). Attempting a swim from the plan back to the 70’ mark will extend your bottom time beyond the capacity of your 50% bottle.

On-going exploration of the PB4Y by PugetSound Divers

Over the course of 2007 PugetSound Divers recorded more than 14 hours of bottom time on this plane. This is one of the more fun wrecks in Lake Washington and sitting at 145’ deep it is rather easily accessible.

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Click here for more information about the PB4Y and this picture.

As with all the sensitive wrecks in the lake there is no need to anchor and further more we ask that all dives to this site use a light drop line and drop at least 50’ from the plane. Because the wings do not give a good signal on the depth sounder our team drops in on the tail placing the drop line in 160’ and swimming up the slight grade to the plane. This positioning will ensure that you do not accidently drop your shot directly on the wreck.

We will post video of this site soon.