FLIGHT International, 28 November 1974 745 Right, the pressurised Beech Baron BSSP (see news item); below, one of Airtransit's six Twin Otters at Rockliffe, Ottawa ;AIS TRANSPORT.. LIGHT COMMERCIAL & BUSINESS a The Airtransit operation I N MAY 1971 the Federal Government of Canada directed its Ministry of Transport to plan, develop and evaluate a Stol commuter air system. The Ottawa-Montreal corridor was chosen as the site for the trial, as competition from every other mode of transportation exists along the route, with more than 2*2 million persons travelling between the two cities every year. Dense air traffic, to test the system's compatibility with conventional air traffic, was a require ment, as was the presence of a wide range of weather conditions. The routeing had to lead to city-core areas where "Stolports" could be built. From the outset it was decided that the trial operation had to test the complete Stol rapid-transit system from city-centre to city-centre with minimum inconvenience and maximum speed. Most of the pasengers would be business people on day-return trips. Criteria for both sites were space, convenience and easy access to the centre as well as minimal noise dis turbance to surrounding communities. The Twin Otter requires only a 2,000ft runway and it was found possible to construct the whole Stolport in only 44*2 acres. Of all the sites considered in Ottawa the ex-RCAF base at Rock- cliffe was judged the most suitable. In Montreal the Victoria car park from the Expo 67 site was chosen and the Stolport was constructed in less than a year. Airtransit Canada, a wholly owned subsidiary of Air Canada, was incorporated on June 19, 1973, to operate the services for two years using six de Havilland Canada Twin Otter Series 300s. The pilots were chosen in late 1973 and underwent extensive ground and simulator air training courses. Several weeks of test flying demonstrated to the residents that the Stolports would be less of a noise nuisance at 500ft distance than a bus at 100ft. The Twin Otters have been modified to improve safety and Stol capability. Changes include high-capacity disc brakes, anti-skid braking system, wing spoilers, propeller de-icing, electrical and hydraulic system improvements, emergency brakes, propeller auto-feather delay and improved powerplant fire protection. Eleven larger seats replace the original 20 and toilet facilities, a coat rack and air-conditioning have been added. The cruising altitude is between 3,000ft and 8,000ft and as this is the height band of light aircraft and piston- engined commercial aircraft the Twin Otters are fitted with an area-navigation (RNav) system to allow them to fly pre-selected routes off the airways to avoid congestion. The RNav system selected allows certain routes to be flown on autopilot by the insertion of a programmed card into the system before the flight. Air traffic controllers and pilots choose a flight plan that does not conflict with other air traffic, and the requisite card is then fed into the RNav computer. Approaches are made at 6°-9° and the aircraft and Stolports are fitted with Co-Scan MLS equipment. To allow normal airways operation the aircraft are equipped with full IFR instruments including flight recorder, elec tric servo altimeter, radio altimeter, and an air data acquisition system. The trial started early in July and the Twin Otters fly hourly from each of the two cities. The $20 fare covers only the direct operating costs; there is a $24 million annual Government subsidy. Because of the size of the aircraft and the short flights there are no cabin attendants. Baggage space on the air craft is limited, but suitcases can be carried. The system was designed to transport passengers city- centre to city-centre, and ground transport to and from the city cores is included in the fare. "Stolmobile" services leave the Hotel Bonaventure, Montreal, 15min before flight time and the Holiday Inn, Ottawa, 30min before flight time. All seats have to be reserved. Initial indications are that the Stol service is catching on amongst the business community. The present petrol problems are making the Stol service more popular; more and more commuters prefer to travel city-centre to city- centre at Airtransit's expense and to leave their own cars at home. B«ech pressurises the Baron Beech has introduced a pressurised version of its Baron twin, FY1974 sales of which showed a 27 per cent improvement in dollar terms over 1973 figures. The six-seater B58P is powered by two turbosupercharged 310 h.p. Continental engines and deliveries are expected next spring. Air Centre taken over The $2 • 1 million lawsuit filed against Aerospatiale by US Corvette distributor Air Centre of Oklahoma has been dropped following the assumption of control of the distributor by the manufacturer. The president of Air Centre is to leave and a new board is to be elected. More S-61s for British Airways British Airways Heli copters has ordered three more Sikorsky S-61Ns for delivery in the second half of next year. Ambulance flying When four members of the crew of the container ship Asiafreighter were poisoned by leaking chemicals, Thurston Aviation's Islander and Navajo Chief tain were called in to fly the casualties from RAF St Mawgan to London.