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Thus far, the Tutor had seemed to be entirely conventional in both construction and operation, but as we taxied out to the run-up point, I was surprised when Steve announced he would lean the mixture prior to take-off. Directly in front of the pilot is a small table that indicates what the fuel flow should be at maximum power for various altitudes, and as Sibson is only 100ft ASL, we used the figures for sea level, which equated to a fuel flow of 55 litres per hour.

With the parking brake on and prop set for max rpm Steve smoothly opened the throttle up to 25 inches of manifold pressure and then slowly leaned the mixture until the gauge was indicating the requisite fuel flow. With the rest of the checks completed and the flaps set to the take-off position, I taxied out onto Sibson's runway 07 and opened the Lycoming up to full power. Acceleration was good but not great, although, to be fair, as the fuel tanks were full we were only about 30lbs below the maximum take-off weight of 2,182lb. A reasonable amount of right rudder was required to track the centreline and as the needle of the ASI swept through 60kts a touch of backpressure on the stick lifted the Tutor off the ground and into the air. The airspeed increased rapidly towards the Vy of 80kts, at which point I retracted the flaps and eased the stick back to hold 80 with the VSI indicating just over 1,000ft/min. Having turned towards the south in order to keep clear of the busy Wittering MATZ, I continued the climb up to 6,000ft, as I was keen to try my hand at aerobatting the Tutor. But first I needed to explore some of the Tutor's basic handling characteristics. Stability around all three axes was good, with the longitudinal stability in particular being very positive. Control around all three axes was equally satisfactory, with light, powerful ailerons, a slightly heavier though no less authoritative elevator and an effective rudder. Control harmony was also spot on, with the ailerons being the lightest control and the rudder the heaviest.

I was slightly surprised at how little rudder was required in flight, but then realised that there is an interlink between the ailerons and the rudder. Pushrods are used for the elevator and ailerons consequently (and unlike designs which use cables for the primary controls), there is no 'slop' in the control circuit at all. This is one of the great advantages of using pushrods over bellcranks and cables, and is almost certainly a by-product of Grob's long association with sailplane design and manufacture. A look at the cruise performance came next, so on Steve's recommendation I set 19 inches of manifold pressure with the throttle and then eased the prop lever back to 2500rpm. The indicated airspeed quickly settled on 100kts, for a fuel flow of just over nine gallons an hour. Frankly, I was a little bit disappointed by this, as (on paper at least) I felt that a modern composite airframe fitted with a laminar flow aerofoil and powered by a 180hp engine turning a three-blade constant-speed prop should really do better. However, the Tutor's canopy is fairly tall (in order to accommodate the 'bone domes' worn by the instructors and students) and this must increase the drag. And while we're on the subject of the canopy, I have to report that the large blind area caused by the design of the windscreen frame and canopy arch continued to make itself felt. I thought that this was a great shame, as overall the visibility is excellent and only marred by something which probably could have been avoided. A look at the slow end of the speed envelope revealed no surprises, with the Tutor exhibiting exemplary stall characteristics. Even with the flaps fully retracted there is plenty of pre-stall buffet, while with full flap the airframe really shakes! The difference in the stall speed with flaps fully extended was only about four knots slower than a clean stall, and the ailerons remained effective even deep in the stall. The Tutor's spin behaviour was equally benign, with recovery from a two-turn spin beginning almost immediately spin recovery action was taken.

Moving swiftly on to the aerobatic part of the flight, Steve suggested that he demonstrate each manoeuvre first, and that I should then try to replicate that manoeuvre. Steve started off with a loop, which I managed to copy quite successfully, before moving onto a barrel roll. Unfortunately, my barrel roll was far from pretty, so before progressing to the half Cuban, Steve talked me round a much more elegant barrel roll. Steve is a vastly experienced instructor and it was a real pleasure to be taught by a master.

After a reasonable reverse Cuban and a passable half Cuban, we just had time for a pair of flick rolls before returning to Sibson for a couple of circuits. All the circuits were essentially similar and concluded with respectable landings. The Tutor is easy to trim and is very speed-stable. I flew at 80kts on the downwind leg and 70 on final, bleeding back to a 'last look' speed of 65, with the flaps set to the 'land' setting of 45°. All three landings were perfectly acceptable, and Steve was soon on his way back to Cranwell.

I often find that, when writing up these reports back in the office, that there are one or two aspects that I would have liked to have looked at in greater detail. In this instance I was curious to find out if the landings are fundamentally different if full flap is used. Luckily RAF Cranwell is just up the road and Steve very generously agreed that we could fly a second sortie from there.

Earlier in the article you may recall that I was less than impressed by the 'cushion' method of adjusting the seat. However, when I visited the safety equipment section at RAF Cranwell to be outfitted with my flying suit, parachute and helmet, this system began to make a lot more sense. The different sized cushions (for both seat back and seat pan) are colour coded and along with the adjustable rudder pedals offer a very wide range of adjustment. Furthermore, this system is cheap, maintenance-free and really does work very well. I think that it was the idea of having to carry different sized cushions when landing away from an EFTS base that had initially under-whelmed me, but when the aircraft is operated in its normal environment, I have to admit that it did make a lot more sense.

After another session of general handling and exhilarating aerobatics, we returned to the Cranwell circuit for a look at landing with full (60°) of flap, instead of the recommended setting of 45°. As expected, this did produce a slightly shorter flare, although it didn't seem to make as much difference to the landing as I'd predicted. The rather stiff-legged undercarriage is certainly no flatterer, and I failed to produce a real 'greaser', although again all the landings were perfectly acceptable.

In conclusion, I think that the Tutor is an excellent trainer. It possesses reasonable performance and excellent handling, combined with a relatively low-maintenance airframe and large, comfortable cockpit. There are a few areas where improvements could be made, most noticeably in terms of the visibility, as the blind spot caused by the over-large canopy arch and windscreen frame is definitely sub-standard. Overall though, I was quite favourably impressed with the Tutor, and wouldn't mind owning one. I'll certainly be keeping an eye out at the various aircraft auctions when the Tutors are eventually pensioned off!

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