Depth
25.5 m
Dive profile
Move over the chart to inspect depth values.
Comments
2021-08-12 D0824 M451
After work dive on Thursday 12.8.2021 evening on Hinkki boat of diving club Kupla from Porkala Marina to the wreck of M-451.
It was 6 divers: me, Olli, Mikko V., Kimmo, Juhani, Walter. Tuomas had also pallned to come but bailed out.
We had agreed that boat would depart at 17:00. Weather looked a bit suspisicios, there were thunderstroms and random rain in Espoo, but weather services showed that we should not have rain or thunder out at the Porkala Peninsula sea.
I had all my diving gear ready at home. I planned to use my D10 tanks that had some weak Nitrox in them. The Shearwater AI transmitter proved to be broken due to a failed Over Pressure Valve (OPV). I had contacted Shearwater support and they were going to ship me a replacement part is it was still in warranty. It did not quite arrive on Thursday to make it on this dive yet. I had sent the broken transmitter back to them.
I managed to leave home early, and arrived to Porkala Marina 16:15. I had keys to Hinkki boat with me, so I unloaded my gear to the pier, and prepared Hinkki for the dive trip, and then drove Hinkki to the loading pier. As I got the boat to the pier at 16:30, Olli and Kimmo had arrived and we started to load the boat. The others arrived late, and the boat left harbour 10 minutes late at 17:10. We all dressed dry suits on before departure because rain was a possibility, but it did not rain. It was quite warm, low waves and very light breeze. Olli drove the boat to the site.
The boat ride to M451 location is just 30 min. This summer there were no fixed buoys at the wreck, but we had accurate location and the wreck shows very clearly on sonar. So we dropped our own shotline next to the wreck. Olli called to the military to announce our diving operation starting. The coast guard was on patrol a few miles east from us.
Me, Walter and Juhani were diving first as a triplet. We agreed total dive time 45 min max 25 at the wreck. We all had cameras. We started our dive at 18:03. Decent took 3 min, and the shot was 1 meter from the wreck. I lifted the shot a bit nearer to the wreck. There was a fin next to the shot, but we left it there. It was very dark and visibility about 3 m, water temperature 10 degrees.
First we dived along right side deck the rear end, and looked at the rudder and two propellers. Then on the left side deck to the end of the bridge superstructure. I know from the previous dive that going forward from that point the visibility goes worse as there is a muddy bottom there, so we did not continue. Instead we explored the bridge area and on top there is a big steering wheel, and the rear facing gun. After 28 min back to the shotline and slow ascent, safety stop 3 min at 5 m. Our dive time was 38 min. We could have easily made a longer dive though, so maybe the plan was bit too short.
My left hand dry glove leaked during dive, so the under glove was all wet inside. But water was so warm that this was not a problem. I took some pictures and video.
Mikko was already waiting at the surface as he was diving CCR.
After we got to the boat, Olli and Kimmo quickly kitted up, and I became the captain and dive marshal on duty. We dropped them at buoy and they started they dive 19:02 with 70 min plan. Olli and Kimmo took Oxygen stages with them as this was obviously going to be a deco dive with that plan. We did not anchor the boat and just drove around the buoy. There was a slight current to east, really nice weather, no rain or thunder.
The other triplet surfaced 20:10. We pulled up the shotline and I started to drive the boat back to harbour. The plan was to fuel up and then Olli and Walter would rvie the boat back to our home harbour at Otaniemi.
I unloaded my gear to car and drove back home.
M451 was a WW2 German Navy minesweeper that sank 31st January 1944 south of Mäkiluoto naval fortress due to navigational error. The ship hit rocks and sank quickly. The crew was rescued by the Finnish Navy.
The ship lies at 32 m depth at the military protection zone of Mäkiluoto fortress and requiring entry permission from the navy. Diving this ship requires special permission from the Military Museum of Finland. Our club has all these permissions.
I had dived here previously 17.8.2019, dive 733.
After work dive on Thursday 12.8.2021 evening on Hinkki boat of diving club Kupla from Porkala Marina to the wreck of M-451.
It was 6 divers: me, Olli, Mikko V., Kimmo, Juhani, Walter. Tuomas had also pallned to come but bailed out.
We had agreed that boat would depart at 17:00. Weather looked a bit suspisicios, there were thunderstroms and random rain in Espoo, but weather services showed that we should not have rain or thunder out at the Porkala Peninsula sea.
I had all my diving gear ready at home. I planned to use my D10 tanks that had some weak Nitrox in them. The Shearwater AI transmitter proved to be broken due to a failed Over Pressure Valve (OPV). I had contacted Shearwater support and they were going to ship me a replacement part is it was still in warranty. It did not quite arrive on Thursday to make it on this dive yet. I had sent the broken transmitter back to them.
I managed to leave home early, and arrived to Porkala Marina 16:15. I had keys to Hinkki boat with me, so I unloaded my gear to the pier, and prepared Hinkki for the dive trip, and then drove Hinkki to the loading pier. As I got the boat to the pier at 16:30, Olli and Kimmo had arrived and we started to load the boat. The others arrived late, and the boat left harbour 10 minutes late at 17:10. We all dressed dry suits on before departure because rain was a possibility, but it did not rain. It was quite warm, low waves and very light breeze. Olli drove the boat to the site.
The boat ride to M451 location is just 30 min. This summer there were no fixed buoys at the wreck, but we had accurate location and the wreck shows very clearly on sonar. So we dropped our own shotline next to the wreck. Olli called to the military to announce our diving operation starting. The coast guard was on patrol a few miles east from us.
Me, Walter and Juhani were diving first as a triplet. We agreed total dive time 45 min max 25 at the wreck. We all had cameras. We started our dive at 18:03. Decent took 3 min, and the shot was 1 meter from the wreck. I lifted the shot a bit nearer to the wreck. There was a fin next to the shot, but we left it there. It was very dark and visibility about 3 m, water temperature 10 degrees.
First we dived along right side deck the rear end, and looked at the rudder and two propellers. Then on the left side deck to the end of the bridge superstructure. I know from the previous dive that going forward from that point the visibility goes worse as there is a muddy bottom there, so we did not continue. Instead we explored the bridge area and on top there is a big steering wheel, and the rear facing gun. After 28 min back to the shotline and slow ascent, safety stop 3 min at 5 m. Our dive time was 38 min. We could have easily made a longer dive though, so maybe the plan was bit too short.
My left hand dry glove leaked during dive, so the under glove was all wet inside. But water was so warm that this was not a problem. I took some pictures and video.
Mikko was already waiting at the surface as he was diving CCR.
After we got to the boat, Olli and Kimmo quickly kitted up, and I became the captain and dive marshal on duty. We dropped them at buoy and they started they dive 19:02 with 70 min plan. Olli and Kimmo took Oxygen stages with them as this was obviously going to be a deco dive with that plan. We did not anchor the boat and just drove around the buoy. There was a slight current to east, really nice weather, no rain or thunder.
The other triplet surfaced 20:10. We pulled up the shotline and I started to drive the boat back to harbour. The plan was to fuel up and then Olli and Walter would rvie the boat back to our home harbour at Otaniemi.
I unloaded my gear to car and drove back home.
M451 was a WW2 German Navy minesweeper that sank 31st January 1944 south of Mäkiluoto naval fortress due to navigational error. The ship hit rocks and sank quickly. The crew was rescued by the Finnish Navy.
The ship lies at 32 m depth at the military protection zone of Mäkiluoto fortress and requiring entry permission from the navy. Diving this ship requires special permission from the Military Museum of Finland. Our club has all these permissions.
I had dived here previously 17.8.2019, dive 733.
Tanks
Main tank
- Volume
- 10,0 l
- Press. Start
- 220 bar
- Press. End
- 130 bar
- O2%
- 32,0%