JATO (J-toe) or Jet Assisted Take Off is a quick way to get some altitude if you are faced with a short space or obstacles in your take off path. If you read the El Paso articles (Seaplane Story 3) you saw that they had to use JATO to get off that tiny lake.

The JATO containers were referred to as “bottles” (see picture 05a). They are actually solid-fueled rockets. They are not as big in diameter as a 5 gallon can but probably stand 50% taller than a can. On the P5M seaplane 2 bottles were mounted on the rear port hatch and 2 bottles were mounted on the starboard hatch. They were fired as pairs, the lower pair and the upper pair. When airborne and clear of the sea lanes, the bottles were jettisoned.

The most exciting JATO performance I saw was a demonstration piloted by our skipper, Commander “Hap” Hazard. I don’t know what the deal was but there were a lot of Captains and Admirals in the crowd. One of our planes had been stripped of the electronics gear and had a minimum gas load. The only people aboard were the pilot, co-pilot, and a senior mechanic.They started their take off run and almost immediately fired the JATO bottles and I’d swear that plane went almost straight up! You can imagine a fighter plane doing that but to see a giant seaplane was hard to believe.

 

The most exciting JATO run I was involved in was when we were on the way to Japan. We had flown from Hawaii to Kwajalein Atoll, spent the night, and now were ready to head for Midway Island. There was a small harbor formed by a coral reef that looked like it had been enhanced by man. We carried every ounce of gas we could get aboard and were really heavy. The sky was overcast and the sea was choppy. We started our take off run and at the appropriate time, the pilot fired the JATO bottles. We were rushing toward this coral reef but weren’t lifting off. The pilot finally had to abort. By the time we got more JATO bottles aboard, the sea had settled down a little and the pilot had a better feel for the weight and the conditions and we got airborne. That was the hairiest one I got to enjoy.

I was probably aboard for 10 or 15 JATO take offs and was always amazed at how much power you felt when the bottles ignited.

Dave Thomas
March 6, 2012, revised February 16, 2015