FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1946
1946 - 1226.PDF
63* FLIGHT JUNE 2OTH, 1946 Sokol High - efficiency Czech Light Aircraft : Some Impressions of the Mraz MJ Cabin Two-seater The arrangement of a dooron each side, and the use of control wheels rather thancolumns makes entry easy in the Sokol. The lever inthe roof operates the elevator trimming tab, and the brakelever may just be seen in the bottom centre of the dash-board. BACK in the almost forgotten daysof 1939 a surprisingly effectivelittle cabin aircraft, known as the Bibi 550, and produced by the Benes Mraz concern in Czechoslo- vakia, made its appearance in this country. I spent an educative week- end with this device a month or two before war broke out, and felt that, despite various minor faults, it might have found something of a market over here. The price was low, and it carried two people at quite a high cruising speed in more than ordinary comfort. Last week its successor, the Mraz M-i Sokol, or Falcon, was flown over here for a day or two and a re-intro- duction effected, on my side, with considerable interest. This little two- seater—or, if required, three-seater— is an all-wood, side-by-side low-wing cabin monoplane with a manually re- tractable undercarriage and a conse- quently useful performance. The new Walter, Minor 4-111 has a maximum output of 105 b.h.p. and gives the Sokol a top speed of 150 m.p.h. From the pilot's and passenger's point of view the Sokol is nearly everything it should be, and if it can be sold in this country for the sug- gested figure of "less than ^1,400" there should be quite a few takers. The cabin is reasonably roomy, all- round view is fair to good, there is ample luggage space on a tray imme- diately behind the seats, the entry is easy for each occupant, and the handling qualities are '' bright'' even to the point of encouraging aerobatics for which the aircraft is not really in- tended. In a general way, I am against the fitting of wheel controls in any small machine with sensitive ailerons and elevator, since this form of control cannot be so accurately and quickly moved, but the advantages of added leg-room, easier entry and the com- fortably car-like appearance will un- doubtedly tell from the sales angle. This particular demonstrator had, in fact, a somewhat mechanically stiff elevator action, and this, coupled with the sensitivity in somewhat bumpy conditions, caused some temporary over-corrections until my reflexes had accustomed themselves to the general situation. Manual Retraction The Sokol's take-off is shorter than might be expected, and can be hurried, if desirable, by the applica- tion of half or full flap at the last moment. Since these split flaps are mechanically operated by a centrally placed handle, the last twenty-five de- grees of retraction can afterwards be taken off gently. Undercarriage re- traction is completed by means of a large crank between the seats ; no par- ticular effort is involved and, in spite of the eighteen turns required, the legs can be locked home within twelve seconds or so. There is no selector- one simply winds, and the legs are automatically locked and unlocked. "Window" indicators in the wing tell one the necessary story. With a small aircraft expert help may not always be available, so a simple JMRAZ M-I SOKOL IO5i£pTWalter Minor 4-111 Span 32ft lOin. Length 23ft 4in. Weight empty B82lb. All-up weight 1,6541b. Maximum speed 150 m.p.h. Cruising speed 134 m.p.h. Landing speed 40 m.p.h. Range 620 miles. Agents : Aircraft & Allied Enterprises, 10, Hobart Place, Eaton Square, London, S.W.I. mechanical system is very practical. The legs are partially faired and there is no appreciable change of trim when they are moved. Flat Approach In spite of the quite reasonable area af the split flaps, the glide is somewhat on the flat side, and the newcomer will be inclined, at first, to find him- self too high during the approach, which is made at about 60 m.p.h. This kind of approach has the advantage, however, of reducing to a minimum the landing change of angle, so that, once the approach technique has been mastered, the touch-down involves merely a very slight final movement of the wheel. Given a reasonably slow approach speed the Sokol more or less lands itself, and it is delight- fully stable, fore and aft, at 50-60 m.p.h. The stall, flaps up or down, seems to be harmless, though tht Sokol will spin and recover in the usual way. Braking is differential when the central "pull-out" lever is applied, and the taxying view is fair—neither better nor worse than that expected with any tractor-engined cabin air- craft with a conventional undercar- riage. For the benefit of long-legged pilots and passengers it might be a good idea if some form of seat adjust- ment were arranged, though there is, in fact, ample knee-room below th« wheel for any normal person. The word '' Sokol'' means Falcon, and the aircraft will probably be known in this country and the Dominions by that name. H. A. T.
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
