Slingsby Swallow

{{Short description|British single-seat glider, 1957}}

{{Use dmy dates|date=December 2016}}

{{Use British English|date=December 2016}}

{{Infobox Aircraft Begin

| name=T.45 Swallow

| image=Slingsby T.45 Swallow (cropped).jpg

}}{{Infobox Aircraft Type

| type=Intermediate sailplane

| national origin=United Kingdom

| manufacturer=Slingsby Sailplanes Ltd.

| designer=

| first flight=11 October 1957

| introduced=

| retired=

| status=

| primary user=

| more users=

| produced=

| number built=c.117

| program cost=

| unit cost=

| developed from=

| variants with their own articles=

}}

The Slingsby Type 45 Swallow was designed as a club sailplane of reasonable performance and price. One of the most successful of Slingsby's gliders in sales terms, over 100 had been built when production was ended by a 1968 factory fire.{{harvnb|Taylor|1966|p=401}}{{harvnb|Ellison|1971|pp=265–6}}

Design and development

File:Slingsby Swallow LR.jpg

The Slingsby Swallow was a wooden-framed aircraft, covered in a mixture of plywood and fabric. Its high mounted, cantilever, straight-tapered and square-tipped wing had 3.3o dihedral. It was Gaboon plywood-skinned and built around a single spruce spar, with a leading-edge torsion box. Its unbalanced ailerons were fabric covered; there were no flaps but dive brakes could be extended in pairs above and below the wings. The prototype had a 12 m span wing, but all production aircraft had their performance enhanced by an extension to 13.05 m.

The forward fuselage was a plywood semi-monocoque, with the perspex enclosed cockpit immediately ahead of the wing. The strong curvature of the single piece canopy in front of the pilot was later reduced, in Mk.2 aircraft, by extending it forwards.{{harvnb|Ellison|1971|p=214}} In both versions, access was by removal of the canopy and a surrounding fuselage fairing. The whole fuselage was flat sided, but at the rear fabric covering was used. Fixed tail surfaces were plywood skinned and control surfaces fabric covered. Fin and rudder were noticeably straight edged, the unbalanced rudder extending down to the keel. The slightly tapered tailplane was mounted on top of the fuselage and placed far enough forward that the rudder hinge was behind the elevator trailing edge, so that no cutout for rudder movement was needed. The Swallow used a conventional glider undercarriage, a combination of a rubber sprung skid from nose to below the wing leading edge, plus a fixed, unsprung monowheel below mid wing and a small skid at the rear.

Operational history

File:EC-JGR (LECU, 2016-05-01).png

The Swallow flew for the first time on 11 October 1957 and it remained in production for 11 years. About 115-120 Swallows were completed,[http://rcawsey.co.uk/t45.htm List of Swallows] though two were destroyed at the factory in a fire. Part of the uncertainty lies with kits issued by Slingsby for construction abroad. The short-span first prototype was later rebuilt as the Reussner Swift. The RAF used five Swallows, known as Swallow T.X. Mk.1, in its Air Training Corps. Approximately nine Swallows were used by branches of the Royal Air Force Gliding and Soaring Association at airfields across the world, and the equivalent Royal Navy association had four. 25 were sold in Spain, nine in Pakistan and four in Burma. Most of the rest flew with clubs in the UK, though a few went to Commonwealth countries and the USA.

Specifications

{{Aircraft specs

|ref={{harvnb|Taylor|1966|p=401}}The World's Sailplanes:Die Segelflugzeuge der Welt:Les Planeurs du Monde Volume II,{{cite book|last=Shenstone|first=B.S.|title=The World's Sailplanes:Die Segelflugzeuge der Welt:Les Planeurs du Monde Volume II|year=1963|publisher=Organisation Scientifique et Technique Internationale du Vol a Voile (OSTIV) and Schweizer Aero-Revue|location=Zurich|pages=34–36|edition=1st|author2=K.G. Wilkinson |language=en, fr, de}} The World's Sailplanes:Die Segelflugzeuge der Welt:Les Planeurs du Monde{{cite book|last=Shenstone|first=B.S.|title=The World's Sailplanes:Die Segelflugzeuge der Welt:Les Planeurs dans Le Monde|year=1958|publisher=Organisation Scientifique et Technique Internationale du Vol a Voile (OSTIV) and Schweizer Aero-Revue|location=Zurich|pages=115–120|edition=1st |author2=K.G. Wilkinson |author3=Peter Brooks|language=en, fr, de}}

|prime units?=kts

|crew=1

|length m=7.04

|span m=13.05

|height m=1.58

|wing area sqm=13.55

|wing area sqft=

|wing area note=

|aspect ratio=

|airfoil=NACA 633-618 at root, NACA 4412 (mod.) at tip

|empty weight kg=193

|empty weight note= (equipped)

|max takeoff weight kg=318

|more general=

|stall speed kmh=62

|never exceed speed kmh=227

|never exceed speed note=

  • Rough air speed max: {{convert|75|kn|km/h mph|abbr=on}}
  • Aerotow speed max: {{convert|75|kn|km/h mph|abbr=on}}
  • Winch launch speed max: {{convert|70|kn|km/h mph|abbr=on}}
  • Terminal velocity: with full airbrakes {{convert|118|kn|km/h mph|abbr=on}}

|g limits=+5 -2.5 at {{convert|61|kn|km/h mph|abbr=on}}

|roll rate=

|glide ratio=26:1 at {{convert|43|kn|km/h mph|abbr=on}} and {{convert|285|kg|lb|abbr=on|order=flip}} AUW

|sink rate ms=0.7

|sink rate ftmin=

|sink rate note=minimum, at {{convert|36|kn|km/h mph|abbr=on}} and {{convert|285|kg|lb|abbr=on|order=flip}} AUW

|wing loading kg/m2=23.4

|more performance=

}}

See also

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References

{{commonscat}}

=Notes=

{{reflist}}

=Bibliography=

  • {{cite book|last=Shenstone|first=B.S.|title=The World's Sailplanes:Die Segelflugzeuge der Welt:Les Planeurs du Monde Volume II|year=1963|publisher=Organisation Scientifique et Technique Internationale du Vol a Voile (OSTIV) and Schweizer Aero-Revue|location=Zurich|pages=34–36|edition=1st|author2=K.G. Wilkinson |language=en, fr, de}}
  • {{cite book|last=Shenstone|first=B.S.|title=The World's Sailplanes:Die Segelflugzeuge der Welt:Les Planeurs dans Le Monde|year=1958|publisher=Organisation Scientifique et Technique Internationale du Vol a Voile (OSTIV) and Schweizer Aero-Revue|location=Zurich|pages=115–120|edition=1st |author2=K.G. Wilkinson |author3=Peter Brooks|language=en, fr, de}}
  • {{cite book |title= British Gliders and Sailplanes|last=Ellison|first=Norman| year=1971|publisher=A & C Black Ltd|location=London |isbn=978-0-7136-1189-2}}
  • {{cite book |title= Jane's All the World's Aircraft 1966-67|last= Taylor |first= John W R |year=1966|publisher= Sampson Low, Marston &Co. Ltd|location= London}}

{{Slingsby aircraft}}

Category:1950s British sailplanes

Swallow

Category:Aircraft first flown in 1957

Category:High-wing aircraft