General Questions
| The quick answer is – probably not! OV-10s for purchase are very hard to find in any condition. The operators that currently fly them are working hard to hang onto them and get more for parts, and there simply aren’t many airframes to go around. Those who have them are lucky and those who are seriously looking for a plane are finding it a difficult search. Like with buying any warbird, there is a whole lot of horse trading and networking involved in getting one. Most of the Broncos flying today were acquired directly from the government and most were transferred directly to other government agencies like NASA, DOS, or the California Dept. of Forestry and Fire (CDF.) A few were donated to museums. Overseas, the situation is much the same. All we can tell you is that if you’re serious about buying one, like we are 🙂 , you just need to search around and sacrifice lots of propwash to the cloud gods and hope to get lucky. Or better yet, join the OBA and help us find one to be restored, flown, and enjoyed by everyone! |
Aircraft Information
Each aircraft has its own weight and balance information but the following can be used as a starting point.
Empty weight 8260#
Operating weight 10,140# (with internal fuel and crew of 2)
Maximum weight 14,400#
The OV-10 Bronco is a twin-engine, two-seat aircraft designed in the late 1960s by North American Aviation, to fulfill a requirement for three branches of the U.S. military (the Air Force, Marines and Navy, usually referred to as the tri-service requirement.) The design is unconventional, with twin booms, a very large greenhouse canopy, small sponsons for armament, and a cargo area in the center fuselage pod. The original purpose of this airplane was to serve a a Forward Air Control aircraft, although it has been used for a large variety of other roles.
| In the late 1950s and early 60s, it had become obvious the the U.S. military that the O-1, O-2 and similar aircraft were becoming outdated for the observation and light-attack role, which was becoming even more important with the type of warfare that was coming to the forefront in Southeast Asia. The LARA (Light Armed Reconnaissance Aircraft) requirement was issued at the end of 1963 based on this need for a new type of aircraft. This ambitious specification called for a twin-engined, two-man aircraft that could carry at least 2,400 lbs. of cargo, 6 paratroops, or stretchers, as well as be stressed for +8 and -3 Gs. It also had to be launchable from an aircraft carrier, fly at least 350mph, take off in 800 feet and be convertable to an amphibious configuration. Various armament had to be carried, including four 7.62mm machine guns with 2,000 rounds, and external weapons including a 20mm gun pod and Sidewinder missiles. There were 11 proposals and 7 that made the first cut: the Beech PD 183, Douglass D.855, General Dynaics/Convair Model 48 Charger, the Helio 1320, the Lockheed CL-760, a Martin design and the North American/Rockwell NA300. In August 1964, the NA300 was selected. A contract for seven prototype aircraft was issued in October 1964. General Dynamics/Convair protested the decision and built a prototype of the Model 48 Charger anyway, which first flew on November 29, 1964. This was also a twin-boom aircraft that had a broadly similar layout to the Bronco. The Charger, while very interesting in its own right (an aircraft-mounted flamethrower was planned for testing!!) and capable of outperforming the OV-10 in some respects, crashed on October 19, 1965 after 196 test flights and Convair dropped out of contention. The Bronco started flying midway through the Charger’s test program on July 16, 1965 and went on a very distinguished career as the premiere COIN aircraft of the next three decades.
(There is a very interesting book about the Convair Model 48 Charger called Naval Fighters No. 39 which is carried by Aviation Collectibles of Texas – highly recommended.) |
| Sponsons are the small “stub wings” mounted underneath the main wings. Testing of the prototype (which had the sponsons mounted horizontally) resulted in them being redesigned for production aircraft, with the downward angle incorporated to ensure that stores carried on the sponsons jettison cleanly. The sponsons serve two purposes. First, they provide a streamlined housing for the four 7.62mm M60C machine guns, two per side (these are just an airborne version of the standard M60 weapon used by ground troops.) The M60Cs were accessed through a large forward-opening hatch on the top of each sponson. The second function is to provide a place to hang other armament off of externally, from two racks per sponson. Armament was usually seven-shot 2.75 inch rocket pods with marker or high-explosive rockets, or 5-inch four-shot Zuni rocket pods. Sometimes bombs, ADSIDS air-delivered seismic sensors, Mk-6 battlefield illumination flares, and other stores were carried as well. The sponsons can be removed easily and this actually improves flight performance slightly due to the decrease in aerodynamic drag. This is common on most unarmed Broncos flying today. |
The original, or A model, was the definitive version. The B was set up for Germany for use as target tugs, the rear seat was moved to the cargo bay to look backwards out a glass dome replacing the cargo door, and with a target towing pod underneath the fuselage. The C models, as well as the E and Fs, were basically updated versions of A’s that were sold new to other countries with some mostly internal equipment modifications. The D was the second-generation Bronco developed and flown only by the US Marine Corps, created by taking an A model airframe and performing extensive modifications. The D added a powerful Forward-Looking Infra-Red night-vision system with a camera mounted in a turret under an extended nose. It is easy to differentiate a D model from an A. The D has a long nose with a ball turret underneath, while the A has a short rounded nose. The D also has bigger engines, so it has larger fiberglass props that can be distinguished by their rounded tips. The A has squared-off aluminum props. Other noticeable external differences are the square chaff dispensers midway down the booms on the D model (often covered with a plate when not in use) and infrared-suppressive exhaust stacks (they take air in the front and mix it with the exhaust before it exits, to reduce the heat given off and thus the ability of a heat-seeking missile to track the aircraft). The D model began life as the NOGS program. The D+ was the next upgrade and consisted of A and D aircraft being extensively reworked at MCAS Cherry Point Naval Air Rework Facility with new wiring and strengthened wings. Engine instrumentation was changed from round dials to tape readouts. The easy way to distinguish the D form the D+ in photos is to look at the tail boom. The D has whip antennas and the D+ has blade antennas.
| There are four semi-circular plates on each wing that rotate up perpendicularly from the top of each wing into the airstream, just outboard of each boom. These are called spoilers. They are mechanically connected to work in concert with, and in proportion to, the ailerons. Their purpose is to kill the aerodynamic lift on the section of the wing they come up on. This causes that wing to drop. The spoilers only come up on the wing that the aileron is also going up on. The end result is a much faster roll rate than is possible with ailerons alone. | |||
| In 1970, the USAF contracted with LTV Electrosystems to modify 15 OV-10As to improve the Bronco’s night and poor weather operational ability, as well as enhance precision strike capabilities. A stabilized nighttime periscope sight, LORAN navigation equipment, a combined laser rangefinder and target illuminator, and a Lear Siegler LORAN coordinator was installed. This combination of equipment was designated Pave Spot, and the aircraft was referred to as a Pave Nail aircraft (since the callsign for the 23rd TASS which flew them was Nail.) The equipment was housed in an external pod located underneath the rear crewmember’s position. The aircraft could put a laser beam on a target for guiding laser-guided weapons, or an accompanying aircraft could make an offset attack. The Pave Nails were flown by the 23rd TASS and often flew in pairs, the high aircraft handling incoming attack aircraft and the low one illuminating targets and acting as the battlefield controller. After the end of hostilities in Vietnam, the Pave Spot equipment was removed. | |||
| NOGS, or Night Observation Gunship System, was the original OV-10D development. The sponsons were removed, the FLIR turret was installed on a lengthened nose to enable night operations, and an M-197 20mm gun turret (similar to that used on the AH-1 Cobra gunship) was added underneath the fuselage between the sponson locations. External wing fuel tanks were also added. Combat trials with two prototypes were quite successful, however funding was not available to continue. The modifications to enable quick incorporation of the gun system was however incorporated into all D models, although funding never came through to actually use the system. After the combat tests, the bigger (1040shp) engines were made standard on D models and the original sponsons were reinstalled. | |||
| NOS, or Night Observation System, was basically the new name for the D model production program that grew out of the earlier NOGS program. The G was dropped as there was no centerline gun turret. | |||
| SLEP, or Service Life Extension Program, was begun in 1985 to make the aircraft strong enough to keep flying in active service beyond the turn of the century. This involved installing better equipment, a new cockpit setup with a computerized management system, structural enhancements, new engines, a new FLIR system, and a new communications system that was as good as any in the world. Other mods included changes to plumbing, wiring, and the restored ability to mount Sidewinder missiles and remove the cargo door for airdrops of soldiers. Aircraft that went through the SLEP conversions are known as OV-10D+. | |||
|
|||||||
| Yes. The German Air Force, which flew OV-10Bs for target towing, developed a version in conjunction with NA and Rhein-Flugzeugbau called the OV-10B(Z) with a single auxiliary turbojet (a GE J85-GE-4) mounted above the center of the wing, in a pod mounted on four struts. This was used to give more thrust during takeoff and target towing operations. The maximum speed increased by about 100mph to 341 knots (392 mph), the rate of climb tripled and it halved the runway used on takeoff. Unfortunately this system never got far beyond the testing stage, it first flew on September 3, 1970 with 11 more aircraft converted during 1971 but only one actually used the pod to any significant extent. | |||
| Many Broncos, especially USMC planes, had the top of their wings painted white, even though the rest of the aircraft was camouflaged. This was done so that while the Bronco was directing other aircraft on ground attack runs, they could see the FAC as they came in from above. Often the fighters would be heading right at the Bronco during a run, so the ability to see each other was more important than staying hidden against the background as seen from overflying enemy aircraft.
A number of different patterns were used on the wing tops. It is also noted that the horizontal stablizer was also painted white in some cases |
Bronco Operators
The primary and original operators of OV-10s were the US Air Force and US Marines. The US Navy flew them for a while in Vietnam. No US military service still flies them. Current US operators include NASA, the State Department and the CDF (California Department of Forestry and Fire.) The BLM used to fly them, as did the BATF – these aircraft have all been transferred to the current US operators. The Washington Dept. of Transportation owns one that hasn’t flown in a while. The Bronco was exported to Germany (OV-10B), Thailand (OV-10C), Venezuela (OV-10E), Indonesia (OV-10F), the Philippines (OV-10A), Morocco (OV-10A), and Colombia (OV-10A). There is an outfit in France that has a privately-owned and flying OV-10B, and there are several on static display in museums around the US and the rest of the world.
There is mention in several magazine articles that South Korea flew Broncos. This is not correct. They did request OV-10D’s after the 1983 NOGS demonstration tests but the request was turned down by the State Department.
| Only overseas. The US Marines retired the last US military Broncos in July 1994. | |||
|
|||||||
| This is a rumor that has appeared on a couple of websites and in articles in past years, starting right after the Branch Davidian standoff in Waco TX. It seems that the fact that the Bureau of Alcohol, Tobacco and Firearms (BATF) acquired Broncos for anti-narcotics operations started a lot of unsubstantiated stories online and elsewhere, primarily among the conspiracy-theorist community. The BATF has long been a favorite target for anti-government sentiment, however all the stories we’ve seen relating to OV-10s being acquired by government agencies allegedly for use against U.S. citizens have been wildly inaccurate and usually conflict with both known facts and common sense. Stories like this should be treated as amusing and nothing more.
The Broncos the BATF acquired in 1994 were later transferred to the State Dept. where they are operated to spray herbicide on coca fields in South America. These airframes were in fact acquired by, and are FAA-registered to, a fictitious company, which has helped feed some of these rumors. Even today, many details of the State department operations are kept secret. This secrecy is not because these aircraft are to be used against American citizens, or even that what they are doing is a secret. It is because there are legitimate safety concerns on behalf of the employees of this program due to the types of people whose crops are being sprayed! These aircraft often take fire ranging up to anti-aircraft missiles during spray missions, but they are required to remain unarmed. Due to treaties and other legal regulations, U.S. aircraft cannot fly armed missions in other countries. Therefore they depend upon the host country’s military to provide armed gunships for escort. You may wish to read about our tour of their operations base to find out more about these aircraft. |
|||
North American Aviation was incorporated in Delaware in 1928 and built many famous aircraft including the P-51 Mustang, B-25 Mitchell bomber, F-86 Sabre, XB-70 Valkyrie, and X-15 experimental rocket plane. The NA300 was North American’s entry into the US Navy’s Light Armed Reconnaissance Aircraft (LARA) competition, and was declared the winning design in August 1964. It first flew under the designation YOV-10A Bronco on July 16, 1965. In October 1966 the first production order for the OV-10A was placed.
On September 22, 1967, North American Aviation Inc. and Rockwell Standard Corporation of Pittsburgh (a manufacturer of automotive components and builder of the Aero Commander series of civil aircraft) merged to form North American Rockwell Corporation.
By September 1969, the US Marine Corps had 114 OV-10A Broncos in service, of which 18 were on loan to the USN. At this time, the USAF had 157 OV-10A’s. Most were dedicated to Forward Air Control duties in Vietnam.
In 1973, the corporation changed its name to Rockwell International Corporation. The Aerospace portion of the business was called North American Aircraft Operations and appears to have devoted much of its time to the multi-billion dollar development program of the B-1 bomber, as well as the development and building of the (then-futuristic) Space Shuttle.
On 6th December 1996, Boeing completed a US$3.1 billion acquisition of Rockwell Aerospace and Defence. Following the takeover, it was briefly known as Boeing North American but was subsequently absorbed into McDonnell Aircraft and Missile Systems (McDonnell Douglas was another Boeing acquisition – itself a merger between famous aviation companies).
Today the Bronco is “owned” by The Boeing Company, but as a new Bronco has never been built under that name, convention has it that Broncos can be referred to as either a “Rockwell OV-10 Bronco” or a “North American OV-10 Bronco”.
Brendan Searle provided this info.
Weapons
| The pair of stub-wing sponsons contain four M60C (7.62 NATO) machine guns, each with 500 rounds of ammunition, and four weapon attachment points. A fifth attachment point is under the fuselage centreline between the sponsons.
Stores that can be carried on the underfuselage and sponson stations include:
The OV-10A can also carry one AIM-9D Sidewinder under each wing on hardpoints outboard of the prop arc. The OV-10D lost this capability, but it was restored with the SLEP upgrade. The centerline station (only) can carry one 150 US gallon or one 230 US gallon drop tank. The under wing hardpoints can each carry a 100 US gallon drop tank. The five self sealing bladder wing tanks totalled 252 US gallons. The OV-10D can optionally carry a turret-mounted General Electric M-197 20mm cannon with 1,500 rounds on the centreline hardpoint with the sponsons removed in the NOGS configuration. This was never flown operationally, despite a very successful two-month combat test program. There are photos, videos, artwork, and even a model kit (AirFix’s OV-10D NOGS) depicting OV-10s carrying AGM-118 Hellfire anti-tank missiles. While VMO-2 did conduct captive-carry trials with inert Hellfires, the missile was never cleared for use on the Bronco. For everything you would ever wish to know about aircraft weaponry, we highly recommend visiting The Ordnance Shop. Lastly, 5 to 6 paratroops can be delivered with rear seat and cargo door removed! (The cargo bay was designed to carry two stretchers and an attendant – but conditions would generously be described as cramped in this configuration.) Brendan Searle provided this info. |
| No. The OV-10 is not intended for nuclear weapons delivery, nor has it ever been (or will it ever be) tested or certified for the delivery of nuclear weapons. Theoretically an OV-10 has the payload capacity to deliver a tactical nuclear device, but both the delivery and escape options would be limited. In short, it would be just too slow to escape the blast unless the payload was a stand-off weapon (i.e. a missile) and in that case there are far better delivery platforms available.
In the 1960’s, the MK 28 was the smallest of the common US air drop nuclear weapons. This weapon was initially certified for use by F-84, F-86, F-100, F-101, F-104, as well as a number of strategic bombers and carrier based aircraft. The weight of the device is comparable to the 230-Gal centerline drop tank. The MK 28 was a modular weapon with interchangeable fusing, tailcone and explosive core of differing yields down to 10 kilotons. The MK 28RE (parachute retarded external carriage) configuration could by fused as a “laydown” weapon where the bomb is dropped to the ground from as little as 50ft and detonates after a pre-set time delay up to a few hours later. For the more tactically useful free-fall delivery method, the OV-10 ceiling of 30-35,000 ft, comparatively slow airspeed and lack of high altitude bomb-sighting would make it a poor delivery choice when more suitable supersonic aircraft, such as the F-4 Phantom, were on hand with crews that had already been trained in the task. Brendan Searle provided this info. |
Flying The Broncos
Yes. If it fails right after takeoff at low speed and high throttle, however, a Bronco will easily roll several times in a couple of seconds and the crew is advised to eject quickly in such circumstances. If it happens in normal flight, a successful landing can be made by following the normal engine-out procedures. Single engine landings are not a problem as long as there are several thousand feet of runway available. There is no need to eject from a single engine Bronco as long as airspeed and altitude can be maintained. The pilot might have to jettison weapon stores or the external fuel tank if still full to continue flying the plane.
| We know that one of the most useful units of measurement in Vietnam was how many cases of beer could be loaded in the back of an OV-10 on the return trip from delivering crews to their R&R assignments. Unfortunately we have yet to confirm exactly how much beer that actually is. The cargo capacity of an OV-10A is 3,200 pounds and 110 cubic feet. Figure it out! ;^) |
Bronco History
Here is a brief synopsis of significant dates in OV-10 History:
|