Glomb

{{for|the name|Glomb (surname)}} {{Use American English|date=October 2024}} {{Use dmy dates|date=October 2024}} {{Infobox weapon | name = Glomb | image = Pratt-Read LBE-1 Glomb.png | image_size = 300 | caption = Pratt-Read LBE-1 Glomb | origin = United States | type = [[Glide bomb]] | is_missile = yes | service = 1944–1945 | used_by = [[United States Navy]] | wars = [[World War II]] (test only) | manufacturer = | production_date = | number = }} '''Glomb''', from "[[glide bomb]]", was a project undertaken by the [[United States Navy]] during [[World War II]] to develop an [[unmanned aerial vehicle|unmanned aircraft]] for delivering [[aerial bomb|bombs]] to high-value, well-protected targets without risk to [[aircrew]]. The project proceeded through the war, producing several prototype aircraft, but technical limitations meant no Glombs saw operational service and the program was cancelled at the end of the war.

==Design history== During late 1940, the [[United States Navy]] began studying the possibility of developing [[military glider|gliders]] that would be remotely controlled to carry bombs to a target, reducing the risk to aircrew.<ref name="DS">Parsch 2005</ref> In 1941, the [[Joint Air Advisory Committee]] approved the creation of the Glomb project, recommending that the project be conducted as a joint effort between the [[United States Department of War|War Department]] and [[United States Department of the Navy|Navy Department]].<ref name="Ord">Ordway and Wakeford 1960, p. 180.</ref> On 19 April the Navy's [[Bureau of Aeronautics]] officially initiated a project office at the [[Naval Aircraft Factory]] (NAF) for development of an operational glide bomb.<ref>Grossnick and Armstrong 1997, p. 105.</ref>

In 1942, a defined specification was prepared for a series of [[glider aircraft]] capable of carrying either {{convert|18000|lb}} of explosives or {{convert|3000|USgal}} of fuel in a [[tanker aircraft|tanker]] configuration; by 1944, when such an aircraft was able to be built, the course of the war meant that such a large aircraft was no longer needed.<ref name="Ord"/> However a project for a smaller glide bomb, based on a modified production glider, was underway, with tests of [[radio command guidance]] being undertaken using modified training gliders,<ref name="Ord"/> starting in September 1942.<ref name="Trim">Trimble 1990, pp. 269–270.</ref>

The [[Taylorcraft LNT|Taylorcraft XLNT-1]], [[Piper LNP|Piper XLNP-1]], [[Aeronca LNR|Aeronca XLNR-1]], and [[Waco LRW|Waco XLRW-1]]<ref name="DS"/> were evaluated under Project George,<ref name="Trim"/> with the Taylorcraft model, designated XLNT-2 in definitive Glomb form, being considered the most suitable.<ref name="DS"/> It was modified with a [[tricycle undercarriage]] to allow for ease of towing during takeoff, and [[television guidance]] was used, the only form of guidance that was sufficiently reliable given the state of the art at the time; a payload of up to {{convert|4000|lb}} could be carried.<ref name="Ord"/>

The results of the trials were considered sufficiently satisfactory for specifications for a production Glomb to be produced by the Naval Aircraft Factory and released to manufacturers for proposals in August 1943.<ref name="Ord"/>

==Developmental testing== [[File:Piper LBP-1 Glomb.png|thumb|left|Piper LBP-1 Glomb]] The specifications produced by the NAF called for a payload of {{convert|4000|lb}} to be carried by the definitive Glomb, with a [[radius of action]] of {{convert|350|nmi|mi km}}; the [[glider tug|towing aircraft]] specified as a baseline was the [[Grumman F6F Hellcat]].<ref name="Fried">Friedman 1982, p. 201.</ref> In September, contracts were awarded to [[Pratt-Read]], [[Piper Aircraft]], and [[Taylorcraft Aircraft]] for production of the [[Pratt-Read LBE|LBE]], [[Piper LBP|LBP]], and [[Taylorcraft LBT|LBT]], respectively,<ref name="Ord"/> for 100 aircraft of each type.<ref name="Fried"/>

In September 1944, the first full, expendable tests of the XLNT Glomb were conducted;<ref name="Ord"/> three aircraft being authorized for use.<ref name="Fried"/> While the aerodynamics and effects of the Glomb were considered satisfactory by the Navy, the guidance system was not, and work on an improved guidance system was undertaken. In addition, studies for the carriage of Glombs on [[aircraft carrier]]s were carried out, but this concept was dropped as no longer needed by the fall of 1944.<ref name="Ord"/>

Continued issues with the guidance system, difficulty of generating electricity to power the onboard systems of the glider, and the changing state of the war, combined with the overall low performance inherent in a glider, led to the program being reduced in 1944; the LBT was cancelled outright in October,<ref name="Fried"/> after production of only 25 aircraft,<ref name="DS"/> while orders for the LBE and LBP were reduced first to 85 aircraft in November 1944, then to 35 each in February 1945.<ref name="Fried"/> Handling issues while landing resulted in the cancellation of the LBP in June 1945,<ref name="Fried"/> and on 14 August, an analysis of the project resulted in the termination of the LBE, the sole remaining Glomb, with only four aircraft having been delivered.<ref name="Fried"/> Work on the [[LBD Gargoyle]] missile, which had been developed as an offshoot of the Glomb program,<ref name="DS"/> continued, as it was considered more suitable for use by carrier aircraft and required less disruption to incorporate into Navy operations.<ref name="Fried"/>

==References== ===Citations=== {{reflist}}

===Bibliography=== {{refbegin}} * {{cite book|last=Friedman|first=Norman|authorlink=Norman Friedman|title=U.S. Naval Weapons: Every gun, missile, mine, and torpedo used by the U.S. Navy from 1883 to the present day|year=1982|publisher=Naval Institute Press|location=Annapolis, MD|isbn=978-0-87021-735-7}} * {{cite book|last=Grossnick|first=Roy A.|author2=William J. Armstrong|title=United States Naval Aviation, 1910–1995|year=1997|publisher=Naval Historical Center|isbn=0-16-049124-X|url=http://www.history.navy.mil/download/history/app21.pdf|archive-url=https://web.archive.org/web/20000914075403/http://history.navy.mil/download/history/app21.pdf|url-status=dead|archive-date=2000-09-14|accessdate=2013-02-11}} * {{cite book|last=Ordway|first=Frederick Ira|author2=Ronald C. Wakeford|title=International Missile and Spacecraft Guide|year=1960|publisher=McGraw-Hill|location=New York|asin=B000MAEGVC}} * {{cite web|url=http://www.designation-systems.net/dusrm/app1/lb.html|title=LB Series (LBD, LBE, LBP, LBT)|last=Parsch|first=Andreas|date=9 March 2005|work=Directory of U.S. Military Rockets and Missiles, Appendix 1: Early Missiles and Drones|publisher=Designation-Systems|accessdate=2017-12-24}} * {{cite book|last=Trimble|first=William F.|title=Wings for the Navy: A History of the Naval Aircraft Factory 1917–1956|year=1990|publisher=Naval Institute Press|location=Annapolis, MD|isbn=978-0-87021-663-3}} {{refend}}

[[Category:Unmanned aerial vehicles of the United States]] [[Category:World War II guided missiles of the United States]] [[Category:Abandoned military rocket and missile projects of the United States]] [[Category:Cancelled military aircraft projects of the United States]]