Pro Series II Doorknob Estes model rocket kit

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The Pro Series II™ Doorknob rocket is the perfect addition to any rocket enthusiast's collection. It is a 1:5.3 scale model of the single and two-stage Doorknob rockets used by scientists in the 1950s to measure the effects of radioactivity from nuclear testing. The rocket is designed to be both fun and simple to build and fly, making it suitable for rocket enthusiasts of all skill levels. The Doorknob rocket played an essential role in collecting data on the effects of nuclear testing on the ozone layer and possible long-range radioactive fallout. The rocket's ability to capture radioactive data at altitudes of approximately 50 miles made it a crucial tool for scientists during this time. The Pro Series II™ Doorknob rocket comes with two sets of decals, allowing for customization to turn it into a sports model. It is the perfect way to honor the scientific advancements of the 1950s while enjoying the thrill of launching a rocket into the sky.

  • SKILL LEVEL: Advanced
  • RECOMMENDED ENGINES: F15-4, F15-6, E16-4 w/Engine Adapter (sold separately)- D12-3
  • PROJECTED ALTITUDE: 1100 ft. (335 m)

The Estes 1:5.3 Scale Model Doorknob

The Estes 1:5.3 scale Doorknob model rocket is a big and impressive kit that is both simple to build and fun to fly. It will be a hit in both the sport and scale rocket categories. There are two sets of decals available for those who want to turn this scale model into a sports model

Key points:

  • President Eisenhower announced a ban on further nuclear testing on or before October 31, 1958, due to public concerns over nuclear fallout
  • Despite the ban, US scientists carried out the Hardtack Series of tests from April to August 1958
  • Scientists were concerned about damage to the ozone layer and possible effects of long-range radioactive fallout
  • Single and two-stage Doorknob rockets were developed to capture radioactive data at altitudes of approximately 50 miles
  • The Estes 1:5.3 scale model Doorknob is a fun and simple kit to build and fly. Moreover, it has two sets of decals available for customization.

The Ban on Nuclear Testing and the Hardtack Series

Before we start, we need to cover the prehistory of Doorknob Model Rocket. During the mid-1950’s, the US and Russian nuclear testing caused public concerns over nuclear fallout to reach a fevered pitch. In response, President Eisenhower announced a ban on further nuclear testing on or before October 31, 1958.

US scientists disregarded the ban and conducted the Hardtack Series of tests to collect data on radioactivity effects from both underwater and above-ground detonations. The program consisted of 35 detonations in the Pacific Proving Grounds from April to August 1958.

Measuring the Effects of Radioactivity

Scientists were chiefly concerned about damage to the ozone layer and possible effects of long-range radioactive fallout. To measure the earth's upper atmosphere, they developed single and two-stage Doorknob rockets. They could capture radioactive data for analysis at altitudes of approximately 50 miles.

Early results indicated minimal or no damage to the ozone layer from the nuclear testing. Additionally, it's possible that water detonations generated enough ozone to compensate for any loss caused by above-ground testing.

Product specifications
Age recommendation
10+ with adult supervision or 12+
Altitude on max suggested motor
Construction skill
Skill 3 Advanced
76mm x 683mm
Ground support equipment
Not included - Rocket only
Hazard class
Not dangerous goods
Maximum suggested motor
Minimum suggested motor
Motor mount
Outside diameter
18" Parachute
UN Classification
Not dangerous goods
Quantity in pack
Model rocket kit - Advanced
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Manuals / PDF's

Estes Doorknob instruction manual (009720.pdf, 1,456 Kb) [Download]


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