Editing Project HARP (section)

==== Martlet 3A ====
The Martlet 3A was an {{convert|18|cm|in|adj=on}} diameter, gun-fired rocket projectile that theoretically could reach 500&nbsp;km altitude. As HARP's first attempt at a low-cost sabotted rocket system, the projectile was built with [[fiberglass]] or aluminum bodies. A standard 6-inch rocket was bonded to an aluminum case. The rocket nozzle was supported by a pusher plate, which would impart the missile's acceleration through the aluminum wall casing. Fiberglass limited acceleration to 3600&nbsp;[[standard gravity|g]] (corresponding to a velocity of {{convert|3800|ft/s|m/s}} at rocket ignition). The Martlet 3A's original objective was to carry a 40-lbs payload to an altitude of 500&nbsp;km, which theoretically was feasible if the system could be launched at full gun pressures. The rocket motors' solid propellant deformed during firing and the design was never successful, despite several test firings.<ref name=":11" /><ref name="astronautix2">
{{cite encyclopedia
 | title= Martlet 3A
 | encyclopedia= Encyclopedia Astronautica
 | publisher= astronautix.com
 | url= http://www.astronautix.com/lvs/marlet3a.htm
 | access-date= 2016-01-22
 | url-status= dead
 | archive-url= https://web.archive.org/web/20160304000121/http://www.astronautix.com/lvs/marlet3a.htm
 | archive-date= 2016-03-04
}}
</ref>