FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1949
1949 - 0446.PDF
FLIGHT March 10th, 1949 (Right) The instrument panel of B.E.A. S.5Is has been rearranged to accommodate a standard blind-flying layout in the centre. Above it is the compass and an illuminated cross-level bubble. For comparison the orig- inal panel layout is shown in the smaller illustration (above left). The modified Sperry horizon with adjustable pitch and roll datum is seen above. Helicopter Night Mail. . , regular practice flights over Norfolk and intermediate • ground sites at a number of places have been prospected. At the same time intensive instrument-flying training has been in hand in the dual aircraft, and ground sites at a number of places have been prospected. Finally, naviga- tional and landing aids of the type described by Mr. Rowe in his lecture have been under study and development. Results to date have given proof of the pilots' ability to operate in almost any weather conditions, except fog, by day or night, and to fly safely on instruments for consider- able periods. They have also added proof that a scheduled service can be flown with great regularity day or night, and finaUy (and this is most important if helicopters are to compete with land transport) that the service is pos- sible without the use of expensive equipment, large hand- ling crews or elaborately planned and staffed rotorstations. Economy and simplicity of equipment and operation has been one of the guiding principles of the B.E.A. Unit. A new phase in the experiments commenced on Monday February 21st, when the first night mail run took off from Westwood field at Peterborough to make a return flight to Norwich. The timetable is: — Take-ofi, Peterborough, 22.00 Land, Norwich .. 22.56 Take-off, Norwich .. 01.50 Land, Peterborough .. 02.56 This experimental service, carrying dummy mail, will run for one month to enable the Post Office to assess the poten- tial of the helicopter for such duties, and in the hope that a contract will subsequently be forthcoming for mail flights in the reverse (east to west) direction, which is, incidentally, into the prevailing wind. A Good Start Made Though it would be premature to comment on this par- ticular experimental service, it can be said that a good start has been made in spite of trying weather. The only aids in use are V.H.F. homers, a flashing sodium beacon at Norwich and a rotating white beam at Peterborough. Earlier, night-flying practice was carried out at Downham Market airfield, which lies on the track between Peter- borough and Norwich. This station also has a sodium beacon, which can be used as a guide. The night return trip in the small hours is the more difficult on dark nights because the countryside is virtually blacked out. The landing aid used is called a " Wiggimac " (see accompanying photograph and also the diagram on page 115 of Flight, January 27th), named after its inventors, B.E.A.'s experimental engineers, Mr. Wigdorchic and Mr McClements, mentioned earlier. It produces a 100ft circle of light, a darkened wind-direction shadow bar, and a green approach-direction indicator. Later on, for accuracy of navigation, use will probably be made of the Decca track guide, of which an experimental set has already been examined. In the meantime a broad- cast of position every five minutes by the pilot, using V.H.F. and a homing when required, is the routine for this direct service. Pilots' N.F. and I.F. techniques naturally differ a little. It is usual to take off vertically to between 30ft and 60ft then move off on course, using instruments and (if any) horizon. Normal operating speed is 85 m.p.h. I.A.S. and, weather permitting, height is kept at about 1,oooft. A maximum airspeed of 100 m.p.h. can be used if need be. Personal opinions expressed by some of the pilots "indi- cate that flying on instruments is harder work than on a fixed-wing aircraft, but is nothing to worry about so long as the air is calm. In rough air it is definitely tricky and tiring. Any horizon at all is a great help at night, and minimum contact-flight conditions are about 500ft cloud- base and two miles horizontal visibility (assuming there are some lights to see). Load makes little difference to ease of flying, although at the new approved a.u.w. of 5,300 lb the S.51 is reported rather sluggish when getting away. The most drfEcult fly- ing conditions are rough air with limited visibility and a Known as the Wiggt helicopter night-landing floodlight with wind-direction shadow-bar and direction-of- approach indicator is the product of B.E.A. Helicopter
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
