The Boeing P-29 and XF7B-1 were an attempt to produce a more advanced version of the highly successful P-26 . Although slight gains were made in performance, the U.S. Army Air Corps and U.S. Navy did not order the aircraft.
22-465: (Redirected from P-29 ) P29 may refer to: Aircraft [ edit ] Boeing P-29 , an American prototype fighter aircraft Boulton Paul P.29 Sidestrand , a medium bomber of the Royal Air Force Percival P.29 Proctor , a British radio trainer and communications aircraft Vessels [ edit ] HMS Votary (P29) ,
44-573: A Curtiss AT-5A Hawk biplane, featuring a Wright Whirlwind J-5 radial engine, reached an airspeed of 137 miles per hour (220 km/h) equipped with the NACA cowling compared to 118 miles per hour (190 km/h) without it. The idea that the NACA cowling produced thrust through the Meredith effect is fallacious—although in theory the expansion of the air as it was heated by the engine could create some thrust by exiting at high speed, in practice this required
66-520: A Latvian state regional road [REDACTED] Topics referred to by the same term This disambiguation page lists articles associated with the same title formed as a letter–number combination. If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=P29&oldid=1117289482 " Category : Letter–number combination disambiguation pages Hidden categories: Short description
88-709: A cancelled submarine of the Royal Navy INS ; Kadmatt (P29) , a corvette of the Indian Navy Maltese patrol boat P29 , of the Armed Forces of Malta Other uses [ edit ] P29 Highway (Kazakhstan) , part of the AH7 road Papyrus 29 , a biblical manuscript Phosphorus-29 , an isotope of phosphorus Tombstone Municipal Airport , in Cochise County, Arizona, United States P29,
110-597: A drag ring, similar to the P-26A's. It was also fitted with flaps, which the XP-940 lacked. Upon completion of testing of the XP-940, the Army decided on 29 June 1934 to purchase it and two sister ships. The designation P-29 was assigned. After the modified XP-940 was returned to the Army in April 1934, it was assigned the designation YP-29A (serial number 34-24). It eventually was redesignated
132-461: A maximum speed of 220 mph at 10,000 ft (354 km/h at 3,050 m). After testing, the XP-940 was returned to the factory in March for modifications. Due to the tight-fitting canopy and restricted pilot vision from the cockpit enclosure, Boeing reverted to an open cockpit design, retaining the long headrest all the way to the tail. The engine was replaced by a 600 hp (450 kW) R-1340-35 with
154-437: A symmetric, circular airfoil that is wrapped around the engine. In a normal planar airfoil, like a wing, the difference in airspeeds, and their associated changes in pressure, on the top and bottom surfaces, enhances lift. In the case of the NACA cowl, the ring-shaped airfoil is positioned so this lift effect is forward. This thrust does not fully counter the drag of the cowl but greatly mitigates it. The difference in airspeed on
176-510: Is different from Wikidata All article disambiguation pages All disambiguation pages Boeing P-29 The Boeing YP-29 originated as the Model 264 , developed as a private venture under a bailment contract negotiated with the U.S. Army. Development of three prototypes was initiated in the interval between the testing of the XP-936 (P-26 prototype, company Model 248 ) and the delivery of
198-500: The P-29A after an engine change to an R-1340-27 in place of the -35. The cleaner design of the P-29A resulted in a speed increase of 16 mph over the P-26A, but its greater weight cut down on the aircraft's ceiling and maneuverability. Consequently, the Army cancelled an intended P-29A order. The three prototypes were subsequently used strictly for experimental purposes. The second prototype
220-513: The P-26's protective headrest, extending all the way to the windshield frame. The Wasp radial was enclosed in a full NACA cowling rather than the narrow Townend ring of the P-26. One final variant was considered by Boeing, the Model 273 , which was intended for the U.S. Navy as the XF7B-1 . Aside from slight dimensional variations, military equipment carried, and the performance ratings of its Wasp engine,
242-456: The P-29 and XF7B-1 aircraft were ultimately scrapped. Data from Boeing Aircraft since 1916 General characteristics Performance Armament Related development Aircraft of comparable role, configuration, and era Related lists NACA cowling The NACA cowling is a type of aerodynamic fairing used to streamline radial engines installed on airplanes . It
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#1732902696590264-433: The cylinder heads where it is most needed, as opposed to flowing between the cylinders and crankcase where it does little for cooling. Furthermore, turbulence after the air passes the free-standing cylinders is greatly reduced. The sum of all these effects reduces drag by as much as 60%. The test conclusions resulted in almost every radial-engined aircraft being equipped with this cowling, starting in 1932. The test aircraft,
286-457: The first P-26A ( Model 266 ) to the U.S. Army. The Model 264 was an updated and modernized P-26, differing in having fully cantilever wings of elliptical-design, wing flaps, enclosed "greenhouse" canopy, and retractable undercarriage. The landing gear was similar to the Boeing Monomail , the main wheels retracting backwards about halfway into the wings. The fuselage and the tail were basically
308-463: The landing speed of the YP-29 was considered too high for Army operational use and the YP-29 was returned to the factory for the installation of wing flaps. Following service testing by the Army and Boeing, which included trials with controllable pitch propellers, the service test designation was dropped and changed to P-29 after the engine was changed to a Pratt & Whitney R-1340-39. The third Model 264
330-410: The naval fighter was very similar to its Army antecedents. Like the other variants, its enclosed cockpit was eventually modified into an open cockpit, which was considered more acceptable in the era. The airplane made its maiden flight on 20 January 1934 and was flown to Wright Field for Army testing under the experimental military designation XP-940 five days later. During testing, the XP-940 achieved
352-428: The same as those of the P-26. The 264 retained the proven 550 hp Pratt & Whitney R-1340-31 Wasp air-cooled radial , used in the P-26. The armament of one 0.30-cal and one 0.50 cal machine guns mounted in the fuselage sides and firing between the cylinder heads of the radial engine was the same as the P-26A. The first Model 264 featured a long, narrow, sliding canopy, essentially a transparent continuation of
374-449: The second Model 264 to fly. During tests, the following data was obtained: Weights were 2509 lbs. empty, 3518 lbs. gross. Maximum speed was 244 mph at 10,000 ft. Initial climb was 1,600 ft per minute. Service ceiling was 26,000 ft, and absolute ceiling was 26,700 ft. Range was 800 miles. This new cockpit enclosure satisfied the requirement for pilot protection at 250 mph operating speeds. Nevertheless,
396-399: The two sides is due not only to the shape of the airfoil, but also the presence of the cylinders on the inside surface, which serves to further slow the airflow. Nevertheless, the total airflow through the cowl is generally greater than it would be with no cowl as the air is sucked through the cowl by the air flowing around it. This has the side-effect of keeping the fast moving air primarily on
418-589: Was completed as the YP-29B with an open cockpit configuration similar to that of the YP-29A. The serial number was 34-25 . The only outward differences between it and the YP-29A were the addition of a one-piece wing flap similar to that of the YP-29, an additional one degree of dihedral in the wing, and an oleo tail wheel assembly similar to that of the YP-29. The YP-29B was sent to Chanute Field in Illinois for service testing. It
440-399: Was completed with a large and roomy glasshouse enclosure around the cockpit and, in addition, the tailwheel was housed in a different fairing. Other changes included an R-1340-35 enclosed in an anti-drag ring. The aircraft was delivered to the Army on 4 September 1934 under the designation YP-29 with serial number 34-23. Despite its earlier Army designation and serial number, it was actually
462-504: Was developed by Fred Weick of the National Advisory Committee for Aeronautics (NACA) in 1927. It was a major advancement in aerodynamic drag reduction, and paid for its development and installation costs many times over due to the gains in fuel efficiency that it enabled. It won the 1929 Collier Trophy . The NACA cowling enhanced speed through drag reduction while improving engine cooling. The cowling consists of
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#1732902696590484-704: Was eventually redesignated P-29B , adding to the bewildering succession of designations for essentially the same model. An additional variant with a 700 hp (520 kW) R-1535 (civil Twin Wasp Junior) was proposed, as the XP-32 , but was never constructed. Flying for the first time in September 1933, the XF7B-1 (BuNo 9378) was the first monoplane fighter to be tested by the U.S. Navy, although concerns over its high landing speed rendered it unsuitable for carrier operations. All
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