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PISTON-TO-TURBOPROP -- TRANSPORTS (CIVILIAN & MILITARY), WATERBOMBERS, ETC.
[Conv = conversion, Evol = design evolution]
UNBUILT
[Note: Most 1944 UK Brabazon Committee civil Types were intended as Mark 1 recips but evolved into Mk.II turboprops: these were Type I (Brabazon), Type IIA (Ambassador, which remained pistoned engined), Type IIB Viceroy/Viscount, Type III Britannia, Type IIIC Tudor, and Type VA Marathon (flown with AS Mambas). The Marathon has been listed as a testbed. The others have been listed here as unbuilt ... either in their planned piston-engined form or in their intended turboprop evolutions.]
Aermacchi MB-331 (piston engine type?) and MB-331T (turboprop type?) STOL transports
http://www.secretprojects.co.uk/forum/index.php?PHPSESSID=84d64c18713040c1723cc97677693276&topic=872.15
Agusta-Zappata AZ-1 (2 x piston type?) to (turboprop type?) JAWA 1954-55/p161
Airspeed AS.57 Ambassador Mk.I (2 x Centaurus) [Evol] into Mk.2 (4 x AS Mambas)
Airspeed AS.57 Ambassador Mk.I (2 x Centaurus) [Evol] into AS.68 Ambassador (2 x Proteus)
Avro 689 Tudor (4 x Merlin 621s) [Evol] into Mk.II (4 x Theseus)
Beech 65-80 Queen Air (IGSO-540) [Conv/Evol] to turboprop (2 x Allison 250s or Boeing T60s).
Beech Model 120 [Evol] pressurized Queen Air with turboprops (2 x Turbomeca Bastan)
Breguet Br.766 and Br.767, "Deux-Ponts" [Evol] with British turboprops (type/s?)
Bristol T.167 Brabazon Mk.I (coupled Centaurus) [Evol] into Mk.II (coupled Proteus)
Bristol T.175 Britannia (4 x Centaurus) [Evol] into Britannia 100 (4 x Proteus)
Britten-Norman BN-2A Trislander (3 x O-540s) [Conv] to Integrity Aircraft (1 x tail TPE 331)
http://www.flightglobal.com/articles/1999/08/25/55417/commercial-aircraft-directory-part-1.html
Britten-Norman (Pilatus) Trislander (3 x O-540s) [Evol] (turboprop type?)
Canadair North Star (4 x Merlins/R-2800) [Evol] into CL-35 for TCA (4 x RR Dart RD5s)
Consolidated PBY-5A/Canso (R-1830s) [Conv] by Field Aviation (turboprop? unbuilt?)
Consolidated PBY-5A (R-1830s) [Conv] to turboprop study, late '90s
- Study by Len Curreri (abandoned for new-built
ClipperSpirit Project)
De Havilland DH 104 Dove (Gypsy Queen) [Conv] to 2 x 636 shp Astazou X, see Riley Turbo Executive
Dominion Skytrader 800/UV-23A Scout (prototype, IO-720-C) planned [Conv] (Turboméca Astazou XVIs), planned [Evol] into Skytrader ST-1700 Conestoga (PT6A-42s)
Dornier Do 28C [Evol] Do 28A/B deriv with 2 x 530 shp Astazou II turboprops + revised nose
http://www.secretprojects.co.uk/forum/index.php/topic,1911.msg187255.html#msg187255
Dornier Do 24T-3 (Bramo 323) [Evol] into post-war Do-24/72 (3 x Avco-Lycoming T53-21, option for 3 x PT6A-50 or Turboméca)
Douglas DC-6, DC-6B, or DC-7 [Conv] into Aviation Traders Carvair (optional RR Darts) JAWA 1965-66/p129 (also see DC-4M [Evol] into Dart-powered Canadair CL-35, above)
Douglas DC-7 turboprop [Evol] DC-7D (R-R Tyne or Allison ?) and/or DC-7T (R-R Tyne MkI or MkII)
http://www.secretprojects.co.uk/forum/index.php?PHPSESSID=a08e7666221b71b06c589e7c7b47bc9d&topic=5102.msg40500#new
Fairchild C-119C/G/J [Conv] to Turbo Boxcar (Allison T56-A-7s) Wright Paterson feasibility study
http://www.secretprojects.co.uk/forum/index.php?topic=889.0
Fairchild C-123 Provider [Evol] into follow-up concept (4 x 2800 shp GE T64s)
http://www.theaviationzone.com/factsheets/c123.asp
Fairchild C-123 Provider [Conv] to turboprop (engine type unspecified)
-- 1990s proposal by JV betw. US Maryland Air Industries and Bulgarian Novecon
Source: Fliegerrevue, Feb 1993 (p.56)
Fairchild C-123 Provider [Conv] to turboprop (2 x Allison T56A-7 or T56A-15)
-- Conv. by Provider Aviation Services Inc begun Apr 2000, aband. mid 2004 (?)
http://www.oldwings.nl/content/c123t/c123t.htm
Fairchild C-123 Provider [Conv] to C-123T turboprop (2 x Rolls-Royce T56-A-15)
-- 2010 proposal by JV betw. US Fleetwings Aircraft Company and RSA Elmer Group
http://home.janes.com/events/exhibitions/aad2010/sections/daily/day2/sturdy-provider-for-afric.shtml
-- NB: SA Flyer reported that Fleetwing had neg. with Denel to do local work
http://www.saflyermag.co.za/index.php/about/archive-article-list/109-aad-report-2010.html
Fairchild (Canada) F-11
Husky (550 hp Alvis
Leonides) [Conv] to Vazar
Turbo Husky (750 shp PT6A-135)
http://web.archive.org/web/20121022025056/http://vazar.com/fairchild-husky-aircraft-project.html
Grumman HU-16B (Wright R-1820) [Conv] to Conroy Turbo Albatross
- Conroy Turbo Albatross: 2 x 1,740 ehp RR Dart RDa.6 Mk 510*
-- * Rolls-Royce Dart engines and cowlings from Viscount 700
-- HU-16B conv. to be identical to HU-16A conv., N16CA (qv)
-- Jane's All the World's Aircraft 1972-73, Ed. John WR Taylor
Grumman G-64/G-111 Albatross (R-1820-76s) [Evol] to G-xxx (4 x PT6A)
http://www.secretprojects.co.uk/forum/index.php?PHPSESSID=da302984a75066a70bb923add62dd39a&topic=1115.0
Grumman Albatross (Wright R-1820) [Conv] to four engines
- Grumman air tanker conv. for Chile (??turboprops??)
Grumman Albatross (Wright R-1820) [Conv] to Frakes turboprop
- Frakes proposal: 4 x 1,000 shp Pratt & Whitney Canada PT6As
Grumman Albatross (Wright R-1820) [Conv] to 4 x TPE turboprop
- Unknown origin: 4 x 1,100 shp Garrett TPE331,* mid-'90s?**
-- * American Flying Boats and Amphibious Aircraft, pg 243
-- ** Flying, Aug 1994: Chalks G-111s to be TPE331-powered
Grumman Albatross (Wright R-1820) [Conv] to G-111AT Wildfire*
- G-111AT Wildfire: 2 x 1,650 shp Honeywell TPE331-14GR/HR
-- * Marsh Aviation devel. for Wildfire Aircraft LLC
-- Marsh Aviation Wildfire is intended for the water bomber role
Grumman Albatross (Wright R-1820) [Conv] to Albatross Air HU16 LLC G-111(T)
- G-111(T): 2 x 750 shp* P&WC PT6A-29 turboprops or alternatives**
-- * Comparatively low shp makes this project rather unconvincing
-- ** Alternatives Honeywell/Garrett TPE331 or unspecified "G.E."
Grumman Albatross (Wright R-1820) [Conv] to NNC turboprop
- 1999 study (abandoned for new-built ClipperSpirit Project)
Grumman C-1A Trader - planned Turbo Trader [Conv] for Brazil (2 x TPE331)
Lockheed turboprop Super Constellation design studies (led to piston L1649A Starliner)
- L1469 (6000-shp P&W PT2F-1s)
- L1569 (Allison 501s)
- Lockheed L1649B (? turboprop L1649A) Lockheed Aircraft since 1913/p393
Miles HDM 106 Caravan (mockup used HDM.105 parts) to turboprop (eventually Short SC.7) Brown: Miles Aircraft since 1925/p356
On Mark Model 450 [Evol] refined Douglas B-26 exec. transport (2 x 3750-4000 shp Allison 501-D13/D15)
http://www.flightglobal.com/pdfarchive/view/1957/1957%20-%200936.html -- Jane's 1957-58
Riley Turbo Executive (250 hp Gipsy Queens) [Conv] DeHavilland DH 104 Dove to , 2 x 636 shp Astazou X, planned flight 1964
Saab 108-1 MULAS (4 x TIARA T6-320), 108-2, '-3, and '4 with twin turboprops (PT6A-41s)
http://www.secretprojects.co.uk/forum/index.php?PHPSESSID=84d64c18713040c1723cc97677693276&topic=872.0
Short PD.15 transport (4 x Leonides?) to (turboprop type?) Shorts Aircraft since 1900 p466 + p500
http://www.secretprojects.co.uk/forum/index.php?topic=872.msg10585
Short PD.16 transport (4 x piston?) (2 x Bristol Proteus 755) Shorts Aircraft since 1900/p467+p499+p500 http://www.secretprojects.co.uk/forum/index.php?topic=2105.msg20357
Scottish Aviation Twin-Pioneer [Evol] into Turbo-Pioneer (2 x RR Darts, retractable gear, ramp, etc.)
Vickers VC2 Viceroy (2 x Centaurus) [Evol] into VC2 Viscount (4 x RR Darts)
BUILT
Antonov An-2 (ASh-62) [Conv] to An-3/An-3T (940 shp TVD-10 then 1450 shp TVD-20)
Beech 18 (R-985) [Conv] to Volpar VTB-18 Turboliner (TPE 331s or PT6As).
Beech 18 (R-985) [Conv] to Ed West/Hamilton Westwind (engine types vary)
- Westwind I (tricycle undercarriage conversion, PT6A-6, 'A-20, 'A-27)
- Westwind II (tricycle undercarriage, stretched fuselage, PT6A-6, 'A-20, 'A-27)
- Westwind III (original tail-dragger config., PT6A-20, 'A-27, or Lycoming LTP-101 [N432U])
- Westwind IV (tricycle undercarriage, single fin, PT6A-28, 'A-34, 'A-45, or Lycoming LTP-101)
Beech 18 (R-985) [Conv] to Aircraft Industries Inc. (Quebec) Jobmaster (PT6A-20s)
- 1965/66 prototype conversion by Dee Howard, only one other Jobmaster conversion.
Beech 18 (R-985) [Conv] to Beech-SFERMA PD-18-9 (2 x Turboméca Bastan III)
Beech 65-80 Queen Air/L-23F (IGSO-540) [Conv] to P-o-C Model 87 Queen Air/NU-8F (PT6A-6s).
Beech 88 Queen Air (IGSO-540) [Conv] to P-o-C prototype Model 99 (stretched and PT6A-20s).
Beech 88 Queen Air (IGSO-540) [Conv] on production line to King Airs (PT6A-20s).
Beriev Be-30 (prototype, Shvetsov ASh-21s) [Conv] to turboprops (Glushenkov TVD-10s)
Boeing B377 (R-4360s) [Conv] to Aero Spacelines 377MGT Mini Guppy Turbine (Allison 501/T56s)
Boeing B377 (R-4360s) [Conv] to Tracor Aviation 377SGT Super Guppy Turbine (Allison T56-501-D22Cs)
[Also C-97 test-beds for Douglas C-133 (with P&W T34-P-7s)]
Britten-Norman BN-2 Islander (IO-360/IO-540) [Evol] to BN-2T Turbo Islander (Allison 250)
Canadair (Bombardier) CL-215 [Conv] to CL-215T and [Evol] to CL-415.
Consolidated PBY-5A "Canso" (R1820s) [Conv] by Trans-Caribbean (turboprop type?).
[Convair CV-240 conversions/evolutions listed separately]
[DeHavilland/DeHavilland Canada conversions/evolutions listed separately]
Dornier Do 24T-3 (3 x Bramo 323) [Conv] to re-winged Do 24 ATT (3 x PT6A-45s)
Dornier Do 27 Q4 (Lycoming O-470-K) [Conv] to Do 27 T1 (Turboméca Astazou)
Dornier Do 28 (IO-540) [Conv] to re-winged Dornier TNT (TPE 331), Do 28-5X TurboSky prototype (Lycoming LTP 101-600-1A then PT6A-110), and [Evol] production Do 128-6 Turbo Skyservant (PT6A-110).
Dornier Do 28 (IO-540) [Conv] by Aerotech Slovakia (Walter M601Ds)
[Douglas DC-3/C-47 conversions listed separately]
Embraer N-821 Caraja (PT6A-27) [Evol] from Piper PA-31-50 Navajo Chieftain (IO-540).
Fairchild C-123B (R2800s) [Conv] to turboprop C-123T (T56-A-7) for Royal Thai AF
-- 1 x conv (56-4357) by Mancro Aircraft Company (Thai upgrade canc. due to cost)
http://web.archive.org/web/20090504234722/http://www.oldwings.nl/content/c123t/c123t.htm
Grumman G-21 Goose (R-985s) [Conv] to G-21T Turbo Goose (TPE 331 or PT6A-27s, McKinnon and Marshall)
Grumman G-73 Mallard [Conv] to Northern Consolidated testbed (1 x R-1340, 1 x PT6A-6)
Grumman G-73 Mallard (2 x R-1340) [Conv] to Frakes G-73T Turbo Mallard (2 x PT6A-27s)
Grumman HU-16A (Wright R-1820) [Conv] to Conroy Turbo Albatross
- Turbo Albatross: 2 x 1,740 ehp* RR Dart RDa.6 Mk 510**
-- * Some sources say 1,535 shp Mk 510/511, others 2,280 shp
-- ** Rolls-Royce Dart engines & cowlings from Viscount 700
-- 1970 prototype conv. N16CA (G-077, 51-0004 ex-USAF SA-16A)
--
Jane's All the World's Aircraft 1972-73, Ed. John WR Taylor
--
http://www.allaboutguppys.com/cl44/barry_scrap/turbo_albatross.jpg
--
https://c1.staticflickr.com/5/4145/4991266073_e166edec92_b.jpg
Grumman S-2 Tracker - [PT6 Conv] Conair Turbo-Firecat (PT6A-6AF), IMP (PT6A-67CF)
Grumman S-2 Tracker - [TPE331 Conv] Northrop Grumman S-2T (TPE331-15AW), Marsh TurboTracker (TPE331-14GR), Israel Aircraft Industries S-2UP (using Marsh TPE331 kits).
Handley Page HP.81 Hermes IV (Hercules) [Evol] to HP.82 Hermes V (Bristol Theseus).
Handley-Page HPR.3 Herald (prototypes 4 x Leonides Majors) [Conv] to HPR.7 Herald (2 x Dart R.Da.7s)
Harbin (HAMC) Y-11 (Housai HS-6/AI-14R) [Evol] to Y-11T/Y-12 (PT6A-11, later 'A-27)
[PT6A-11s exchanged for 7 x unused JT15D-4 intended for unbuilt Chinese biz-jet design]
Lockheed R7V-1 Super Constellation (4 x R-3350-91s) [Conv*] to R7V-2 (4 x P&W YT34-P-12As)
[* 4 x R7V-1s converted while still on the production line]
Lockheed R7V-1 Super Constellation (4 x R-3350-91s) [Conv*] to YC-121F (4 x P&W YT34-P-6s)
[* 2 x R7V-1 conversions. One YC-121F briefly converted to Allison 501Ds as Lockheed TB]
http://1000aircraftphotos.com/Contributions/4701.htm
Partenavia P68 (I0-360) [Evol] into Partenavia AP68T (Allison 250)
Piaggio P166 (Piaggio-Lycoming GSO-480) [Evol] to P166T/P.166DL3 (Lycoming LTP 101-700) [Conv] to P166DP-1 (c/n 465 & 466 with PT6A-121s).
Pilatus PC-6 Porter (Lycoming IGO-540) [Conv] into PC-6/A Turbo-Porter (Turboméca Astazou) and [Evol] into PC-6/B Turbo-Porter (PT6A) and PC-6/C Turbo-Porter (TPE 331)
Piper PA-31 Navajo (2 x IO-540) [Conv] into P-O-C PA-31T Cheyenne prototype (2 x PT6A-20).
Piper PA-31-50 Navajo Chieftain (IO-540) [Evol] into PA-31T Cheyenne (PT6A-28).
Piper Aerostar (2 x Lycoming TIO-540) [Conv] to Speedstar 850
- Airplane Factory LLC Speedstar 850: 1 x Garrett TPE331 in nose
--
http://www.airliners.net/photo/Airplane-Factory-Speedstar/1759914/M/
Republic Seabee (Franklin 6A8) [Conv] to Turbine Seebee, 1 x derated 400 shp PWC PT6A-20 pusher
- Turbine Seebee prototype conversion C-GNVS (s/n 465), aka 'Sea Hornet'
Republic Seabee (Franklin 6A8) [Conv] to Turboprop Seabee 1 x 523 shp Turbomeca Astazou II L,
- Turboprop Seabee conversion CF-MYT (s/n 1025), completed 1980, first flown 1982
Rockwell Aero Commander 680E (IO-540) [Conv] by PAC to 680T (2 x PT6A-20).
Rockwell Aero Commander 680FL/680P (IO-540) [Evol] into 680T (TPE 331)
Short SC.7 Skyvan Series 1 prototype (IO-520s) [Conv] to Turboméca Astazou IIs.
Swearingen SA26 Merlin (2 x Lycoming TIGO-540) [Conv] to SA26-T Merlin IIA (2 x PT6-20).
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