2014 November 8, page updated and PT 362 tube type corrected thanks to a post by Andy here.

The following images show torpedo tubes on Elco PT boats. Initially 18" torpedo tubes were fitted as can be seen in the images of PT 9 and 10. The 21" Mark 18 tube is seen in most of the other images. The images of PT 196 and 333 show what may be Mark 18 Mod 5 tubes. The image of PT 362 shows unknown tubes. PT 731 is seen with compressed air driven Mark 19 tubes.

Click for full size images

Barge_Elco_Torpedo_Tubes_Smoke_Gens.jpg 269.60 KB 1380 x 994	PT_000_Elco_Early_01.jpg 254.03 KB 1560 x 1253	PT_000_Elco_Early_02.jpg 74.19 KB 799 x 637
PT_000_Elco_Early_03.jpg 425.35 KB 1870 x 2340	PT_000_Elco_Torpedo_Tubes_and_Turret_Rings 224.24 KB 794 x 614	PT_000_Elco_Unknown_Forward_Torpedo.jpg 128.06 KB 1170 x 930
PT_009_aka_PV_70_18inch_Torpedo_Tubes.jpg 377.76 KB 2048 x 1664	PT_010_Elco_Factory_01.jpg 380.90 KB 2048 x 1415	PT_010_Elco_Factory_02.jpg 315.58 KB 1877 x 1512
PT_014_aka_MTB_263.jpg 425.85 KB 1920 x 1607	PT_021.jpg 551.30 KB 1560 x 1255	PT_043_01.jpg 519.09 KB 1560 x 950
PT_043_02.jpg 780.51 KB 1560 x 1119	PT_043_03.jpg 619.36 KB 1560 x 1042	PT_059_Elco_Factory.jpg 241.49 KB 1560 x 1247
PT_061_01.jpg 241.41 KB 1560 x 1251	PT_061_05.jpg 326.42 KB 553 x 800	PT_064_Melville.jpg 249.42 KB 1500 x 1170
PT_066.jpg 397.45 KB 1560 x 1077	PT_070_Foot_Elco_01.jpg 735.03 KB 1873 x 1462	PT_070_Foot_Elco_02.jpg 617.84 KB 1961 x 1417
PT_070_Foot_Elco_03.jpg 136.22 KB 902 x 707	PT_077_Foot_Elco_01.jpg 359.83 KB 2048 x 1687	PT_077_Foot_Elco_Melville_08_Cropped.jpg 49.45 KB 891 x 393
PT_077_Foot_Elco_Melville_10.jpg 793.32 KB 1560 x 1961	PT_077_Foot_Elco_Melville_20.jpg 770.63 KB 1560 x 1930	PT_077_Foot_Elco_Melville_22.jpg 538.12 KB 1560 x 1225
PT_077_Foot_Elco_Melville_23.jpg 524.06 KB 1560 x 1239	PT_077_Foot_Elco_Melville_25.jpg 1.09 MB 1560 x 1619	PT_103_and_105_02.jpg 386.34 KB 1560 x 1251
PT_103_and_105_04.jpg 203.65 KB 1500 x 1197	PT_103_Damage.jpg 528.75 KB 2997 x 2435	PT_105_01.jpg 783.10 KB 1560 x 1979
PT_105_02.jpg 167.89 KB 1500 x 1196	PT_107_Bow.jpg 751.14 KB 1679 x 2801	PT_107_Ron5_July_August_42_01.jpg 144.18 KB 1500 x 1184
PT_108_Chester_Hix.jpg 388.82 KB 1285 x 1744	PT_109_On_USS_Stanton_1.jpg 688.43 KB 2320 x 2891	PT_109_On_USS_Stanton_2.jpg 489.70 KB 1541 x 1216
PT_109_On_USS_Stanton_3.jpg 215.32 KB 1338 x 1016	PT_117_2_Cropped.jpg 137.63 KB 1875 x 433	PT_118.jpg 154.77 KB 900 x 629
PT_121.jpg 130.05 KB 900 x 582	PT_143_Morobe.jpg 1.10 MB 2630 x 2025	PT_149_01.jpg 100.29 KB 1320 x 1050
PT_149_02.jpg 579.89 KB 2404 x 2834	PT_157_01.jpg 559.56 KB 2048 x 1706	PT_196_With_Teeth_Mark18_Mod5_Tubes_Maybe.jpg 52.69 KB 1542 x 821
PT_333_Mark18_Mod5_Tubes_Maybe 70.08 KB 740 x 605	PT_362_Torpedo_Tube_Type_Unknown.jpg 150.56 KB 1387 x 851	PT_731_USSR_Transfer.jpg 136.13 KB 1272 x 988
PT_Elco_80_Foot_103_to_138_01.jpg 437.68 KB 1560 x 1109	PT_Elco_80_Foot_103_to_138_02.jpg 485.32 KB 2048 x 1653	PT_Elco_80_Foot_Factory_Early_1942.jpg 274.74 KB 1600 x 1236
PT_Elco_80_Foot_Stern_Torpedo_Funnels.jpg 576.61 KB 2417 x 2980