N1131Z, Fairchild Funk M62C F-23B, Mitsubishi KI-51 (Allied code name Sonia) Replica Rev. 1

This aircraft as registered with the FAA appears to have two manufacturers and two nomenclatures. N1131Z is not alone in this respect, as the FAA registry shows a total of nine Fairchild Funk M62C F-23A/B aircraft currently in license. The rear fuselage data plate on N1131Z does not help either, as it is imprinted Funk F-23B, Serial No. 9, yet the FAA registration is an F-23A as stated, adding to the confusion.

The genesis of the Fairchild part of this aircraft design goes back to the  Fairchild  of Hagerston, Maryland M-62, a two seat tandem taildragger monoplane trainer first flown in March, 1939. It was used in World War II as the PT-19 two seat primary trainer. More than 8,000 of this type were produced in the USA and Canada. Civilian Pilot Training Program schools operated the M62s and  the military operated the PT-19 and variants. The PT-19 had a tube and fabric covered fuselage with a cantilever wooden taper-shape wing and wooden tail surfaces, plywood-skinned for stiffness. Civilian operated models were known as M62s. There were three main production versions, the PT-19A (M-62A), the PT-26 both with the 200 horspower Ranger 6-440C-5 six cylinder inverted air-cooled engine; and the PT-23 (M62C) version with the Continental R-670-4 radial engine of 220 horsepower. Ranger Engineering Corporation was a division of the Fairchild Engine and Airplane Corporation. The Royal Canadian Air Force version, the PT-26 was called the the "Cornell", having an enclosed tandem cockpit with heater and other changes. The Cornells were lend-leased to Canada via the US Army Air Corps and also carried USAAC ownership markings. The USAAC also operated some PT-19s with the PT-26 style enclosed canopy, adding to recognition confusion. 

Several manufacturers built the PT-19, PT-23 and PT-26 aircraft in the military ramp up toward pre-war pilot training needs. Fairchild and Aeronca built the PT-19 with the 175 horsepower Ranger 6-440C-2 engine. Howard Aircraft of Chicago and the St. Louis Aircraft Corporation built the PT-23, which was identical to the PT-19B except for the Continental R-670-4 engine. Fairchild developed the M-62B version with the 165 horspower Warner Super Scarab radial engine under a NACA cowling because the Ranger engines were committed to military procurements. The M-62B shared the same government ATC (Approved Type Certificate) number with the M-62A, despite different engines.  Fleet of Canada produced PT-23s, but none of them were operated by the RCAF, strangely enough. Fairchild just produced the single prototype XPT-23 and two production PT-23s. 

Wingspan of the PT-19A (M-62A): 36' 0"; wing area: 200 sq. ft.; length of fuselage: 27' 11"; empty weight: 1,845 lbs.; gross weight: 2,545 lbs.; max speed: 132 mph; cruise speed: 120 mph; stall speed: 50 mph; initial rate of climb: 835 ft./minute. Price FAF: $11,230.

The genesis of the Funk part of the Fairchild Funk M62C F-23A/B was the Funk F-23 agricultural aircraft first flown in November 1962, and produced through 1967 by the D. D. Funk Aviation Company. The F-23 was an all-metal low wing taildragger monoplane of constant chord wing and increased wingspan and increased wing area built as a combination duster and sprayer. The Funk F-23 fuselage was constructed from a reworked Fairchild PT-19 fuselage truss and used much of the original PT-19 structure which was sandblasted, re-oiled, primed with a chemical-resistant primer and then metallized. The port and starboard wing panels had dihedral only in the new outer wing panels and, along with their ailerons, these were interchangeable. An "anti-float" tab served the purpose of several degrees of dihedral. The single cockpit was placed behind a 200 gallon chemical hopper  tank and was enclosed and  reinforced for rollover protection for the pilot. Tail surfaces appeared to be identical to the PT-19 size and shape but were of metal construction. The engine in the Funk F-23A was a 240 horsepower Continental W-670-M seven cylinder air-cooled radial without a cowling. Wingspan of the F-23A was 41' 0"; wing area: 287 sq. ft.; length of fuselage: 26' 8" and height: 7' 6". Empty weight was 2,250 lbs.; loaded weight: 4,300 lbs. Max speed: 115 mph; cruise speed: 95 mph; initial rate of climb at gross: 400 ft./minute. The Funk F-23B variant used a Jacobs R755B seven cylinder air-cooled radial of 275 horsepower. The F in the D. D. Funk Aviation Company designation for the F-23 ag aircraft should not be confused with the military 'F' for fighter aircraft. Only 12 F-23A and B ag aircraft were built by the D. D. Funk concern.

It is important to emphasize that the Funk F-23 manufacturer, indeed, was the D. D. Funk Aviation Company of Broken Bow, Oklahoma and Salina, Kansas. Do NOT confuse this company with the Funk brothers, Howard and Joe, who in 1937 designed the Funk B high wing tube and fabric-covered taildragger monoplane first using an inverted, modified Ford model B automobile engine of 60 horsepower. The Funk B was first produced by Akron Aircraft, Incorporated in Ohio before the war; later by the Funk Aircraft Company in Coffeyville, Kansas after World War II. Very few of the Funk B with Ford model B engines remain. Models were also built in 1941 with the 75 horsepower Lycoming GO-145, redesignated as B-75L, and after the war with the 85 horsepower Continental C-85-12 engine as B-85C Funks. As an aside, in 1971 there was a Funk B with the original modified, inverted Ford automobile engine hangared at SZP. I spoke with the owner then who claimed only three Ford model B-engined Funk Bs were operating in 1971. That owner also stated he rebuilt the Ford engine every 100 (one hundred) hours of operation. About 150 total Funk Bs of all models are now on the FAA registry. 

Whereas there are many Fairchild M62/PT-19/PT-23/etc. aircraft in license of various versions, as earlier stated I find only nine Fairchild Funk M62C F-23A/Bs on the FAA registry. N1131Z above and at right pictured has the Continental W-670-M 240 horsepower radial engine under a NACA cowling, according to the FAA database. There are six M62C F-23A and three M62C F-23Bs in the registry. But, two of the M62C F-23As are re-engined with the Jacobs radial engine of two different types: an R755A of 300 horsepower and a Jacobs L4/R755-7 of unknown horsepower. For more pictures of N1131Z, see the aircraft profile pages. It is easy to see both the fuselage elements of the Fairchild PT-19 and the Funk F-23 new wing design in this Fairchild Funk M62C F-23A all-metal 'hybrid' aircraft.

 
N1131Z is painted as a Japanese warbird, but it should be noted it is registered to a cinema corporation. It is probable that it may have appeared in motion pictures or on television. Note the fake bomb under the aircraft fuselage, best seen in the top picture. With 1965 date of manufacture and no supporting documentation available to me, I am still unwilling (bomb or no bomb) to categorize N1131Z as a true warbird.

It might be interesting to have the Asian characters on this aircraft translated. I once heard a story of a woman who sewed a dress for herself copying Asian characters from a Chinese restaurant menu. It was later tactfully pointed out to her while she was wearing the dress that it translated as: "This dish is tasty, but inexpensive". The story may be apochryphal, but it still is good for a laugh.

The picture opposite shows a good view of the new constant chord wing and dihedral just on the outer, interchangeable wing sections. The next below picture shows a closeup of the tandem cockpits with full instrumentation in each. I would be interested in knowing exactly what market this rare Fairchild Funk M62C F-23A aircraft was designed for. Were they converted from Funk F-23s which in fact were converted originally from PT-19s? I do not find any of the 12 Funk F-23 ag aircraft  built still on the FAA register.

REVISION UPDATE, 3 October 2006 

The owner/pilot of this intriguing aircraft contacted me with the full story answering my questions about this aircraft. (I have left the entire prior article above (and below footnote) intact except for the retitle of the article). The conversion of a Fairchild Funk F-23B ag aircraft to serve as a Mitsubishi KI-51 (Allied code name "Sonia") World war II Imperial Japanese army light bomber ground attack replica was first suggested by Malcom Laing, Museum Director of the Texas Air Museum in Slaton, Texas. N1131Z is the second replica converted, and is actually a conversion of a Funk F-23 model using the larger engine, making it an F-23B, despite the FAA designation of F-23A. N1131Z has a Jacobs R755-B2  radial of 275 horsepower. The idea of Mr. Laing's was to put replica aircraft together to fly in airshows as no Imperial Japanese Army aircraft are still flying. The resemblance to a "Sonia" is striking, except the wing not being tapered and with no leading edge slots is entirely different in the replica.

The Mitsubishi KI-51 first flew in 1939 in the China-Burma-India theater in a ground attack role as it was found to be too slow against opposing fighter aircraft. The KI-51 with fixed taildragger landing gear was rough-field capable against China using fields unusable by others. Toward the end of World War II, the "Sonia" was used in Kamikaze attacks. Production of the two seat tandem aircraft total was about 2,385; 1,472 made by Mitsubishi and 913 made by the Army Air Arsenal at Tachikawa, Japan. (Interestingly, I flew into Tachikawa Air Base twice in the late 1960s.)

A few original KI-51 Specifications: Engine: Mitsubishi Ha-26-11 radial piston of 940 horsepower; max speed: 264 mph; range: 659 miles; service ceiling: 27,130 feet, (another reference gives a figure of 31,070 feet).

The owner of N1131Z graciously provided additional information about this illustrated article airplane. It is primarily flown from the front but for training use the back seat has enough controls minus the brakes and mixture controls. Quoting: "--they are a blast to fly. It can out turn a T6 and has at many airshows we've taken it to in Texas. The "Toro" guys all love it and it draws a lot of attention where ever I go. Mine is painted in the "jungle camo scheme" and markings of the 23 Chutai Group. I picked that one because of the 23 tail marking and it being a Funk 23. All the Japanese markings are authentic and indicating "oil here", "no step", "100LL" etc. We had a person fluent in Japanese help with those. The engine in all of them are and will be the Jacobs R755-B2. It is the 275 HP Jacobs and performs great. I burn 11 to 12 gallons/hour at 75% cruise which is a blistering 85 knots indicated. I fly it for two hours and set down before I'm halfway into my 3rd and final hour. I've updated your site with all the numbers for it so that should go through in however long it takes."

I extend a huge thank you to Randolph (Randy) Rogers for this most welcome and interesting information about his successful and rare N1131Z F-23B "Sonia" replica. I look forward to taking more opportunity photos of this striking aircraft.

PLEASE CLICK on the TOP main picture to see the N1131Z Aircraft Profile page and more photos on N1131Z. 

.

 
Footnote, 10 June 2006

A search of the National Transportation Safety Board (NTSB) database revealed two aircraft crashes of Funk F-23 agricultural applicator aircraft, both in Texas. The later accident in 1972 was of Funk F-23 N1129Z, just two N numbers less than the featured N1131Z of this article. Frequently, aircraft manufacturers were assigned a contiguous group of N numbers. The N1129Z aircraft was destroyed, according to the NTSB report. So, it is highly probable because of the N number sequence that N1131Z was converted from a Funk F-23 at some later time to the present Fairchild Funk M62C F-23A configuration using the Funk-originally converted fuselage with the new Funk F-23 design constant-chord longer wings.

This conversion remanufacture (of an earlier conversion) would require removal of the 200 gallon chemical hopper tank forward of the pilot cockpit, removal of the single pilot strengthened rollover enclosure and adding back the forward cockpit with a PT-26 style dual cockpit enclosure and full dual controls, dual instrumentation, etc. The D. D. Funk Aviation Company built just 12 F-23 ag aircraft using reworked PT-19/M62 fuselages from 1962 to 1967, as prior noted. It would appear that N1131Z kept its original date of remanufacture (1965) as a Funk F-23 in the second subsequent remanufacture process as a Fairchild Funk M62C F-23A. 

Contact author Doug Robertson    All Articles    Home