Project : SBD “Dauntless” Photogrammetry Model — (Pt Loma, 200 fsw)

Background

The Scout / Dive Bomber (SBD) was key in the Battle of Midway in June 1942. It was the main aircraft carrier-based scout/dive bomber from mid-1940 through mid-1944. It had the nickname of “Slow But Deadly.” One of the distinguishing features of the Dauntless are the air brakes with perforated holes on the trailing edge. It had two crew (pilot / gunner).

The airplane is 33 feet long, had a 41 foot wingspan, and 13.5 feet high. It was powered by a Wright R-1820-60 Cyclone 9-cylinder air-cooled radial piston engine (1,200 hp) with a cruise speed of 185mph and max speed of 255mph.

The pictures on the left below are of the Dauntless flying above the USS Saratoga which was sunk in Bikini Atoll during Operation Crossroads. I’ve actually been to the Saratoga and have another trip back planned in 2021.

Dive Site

The wreck was discovered by Tyler Stalter back in October, 2019. They believe they have identified the specific aircraft. The plane was on a training mission and trailing a sleeve for target practice when something went wrong. The pilot tried to recover but didn’t. Both crew were lost in the accident.

It is about 200 feet deep and doesn’t have much relief. Given the depth, each dive will be about 5 minutes descent, 20 minutes on the wreck and about 45-60 minutes of decompression. I will probably need 2-3 dives to build the model. The first dive will be primarily orienting myself and surveying the site, the second dive will be primarily taking the photographs and then a third dive if anything needs filling in or a reshoot.

According to Tyler, almost all of the aircraft is at the site but is somewhat scattered about.

This type of site with a lot of debris will make building a photogrammetry model a pretty big challenge but it could also help confirm the identity of the aircraft and some of the debris field. The challenge will come with photo alignment due to the debris field not being compact and likely some featureless spots in between aircraft pieces and no GPS or other identifying marks.

One question that remains is whether or not the sleeve that they were trailing got caught during deployment (or use) and caused the accident.

Some specific photos opportunities for still shots:

  • Landing gear
  • Tire
  • 9 cylinder radial engine. Two propeller blades.
  • Dive brakes / holes
  • Winch in the belly for target towing
  • Find the manufacturer’s plate?

Other Dauntless pictures

When my trip to Bikini got cut short, we headed back and dived a lot of planes in a “graveyard” somewhat near Kwajalein. Here are some of the pictures I took while I was there. Note the two person cockpit, the round airbrake holes on the wing, and the arresting hook on the upside down picture.

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