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Grumman American - Traveler A Tourer at Heart ZS-IXL

April 24, 2018


A Grumman American Traveler, was the second aircraft I ever flew – the first was a Tecnam P92 Echo. In comparison, the Traveler sailed smoothly through the air, with light, responsive yet docile handling, but on the ground that free-castoring nosewheel was a little wayward. Those were my naïve first impressions. Five years later, I was reunited with IXL, and immediately felt at home in this amicable tourer.

 

 

 

The Tecnam Echo is a fantastic ab initio trainer – as basic as they come, with great but forgiving handling. But because it’s an LSA, weighing little more than 300 kg empty, with a high-lift wing, you feel turbulence and get blown about when the wind picks up. I spent my first 50 hours in the Tecnam, and when I took to the sky in IXL to start training for my night rating, I was pleasantly surprised with the lightness of the controls, despite it being twice as heavy as the Echo, and loved how it slid through the air in comparison.

The AA-5 Traveler’s wing is comparatively low drag, and the design’s major selling point is that, with just 150 hp and a fixed pitch prop, it will pull away from any other plane in its class – Cessna’s 172 or Piper’s Cherokee 160, for example. The published cruise speed at 75% power and 9,000 ft amsl is in the region of 147 mph true (approximately 127 KTAS) for the 1975 model, which had slight aerodynamic clean-ups which added 6 kts. The Traveler’s beefed-up brother – the Tiger – which has a 180-hp Lycoming, also driving a fixed pitch two-bladed prop, will outrun pretty much any other four place 180-hp plane in the sky, and even keep pace with some 200-hp retractables or constant speed prop competitors, such as the Piper Arrow.

With Cirrus’s SR22 being the four-seat piston of choice these days, the Traveler’s – and even the Tiger’s – speeds seem pedestrian, but at the time, it was something to brag about. Thus, you’d expect to see more Travelers overhead. The Traveler was built when general aviation had settled in the cruise, and light, four-seat, family cruisers were in high demand – something at which the Traveler, as its name suggests, did well – and its progeny did it even better. However, the Traveler isn’t an ideal trainer, and once you have trained on a particular brand, you’re inclined to stick with it.

The Traveler doesn’t have a fantastic safety record. Between 1976 and 1984, the AA-5 series (Traveler, Cheetah and Tiger) had a total accident rate of 11.9 per 100,000 hours, and a fatal rate of 2.3, far worse than the C172, which scored 7.5 total and 1.0 fatal during the same period. Pilots with low time on type accounted for a remarkably high proportion of AA-5 crashes. Median time on type for the 315 AA-5 accident pilots was only 20 hours, and more than a quarter of AA-5 accident pilots had 10 hours or less on type. Initial climb performance and floating during the landing were the main culprits.

The fibreglass main undercarriage and spring-steel tube holding the free-castoring nosewheel are perfectly adequate, but unlike the indestructible gear on the Cessnas and Cherokees, don’t appreciate the endless circuit bashing of student pilots. The wing too won’t forgive sloppy flying – it likes to be flown to the numbers.

Another reason you don’t see more AA-5s around is that, other than a few Tigers, they were only built between 1971 and 1979. Nevertheless, during those years the factories were busy.

 

HISTORY OF THE AA-5

The Grumman American AA-5 Traveler sprung from American Aviation’s success with its two-seat AA-1 Yankee Clipper. Wanting to add a four-seat model to its product line, in 1969 the company started with a clean-sheet design, designated the American Aviation AA-2 Patriot. The AA-2 failed to achieve its performance goals during test-flying and only one was ever built.

So American Aviation went back to what they knew worked, and simply enlarged both the external and cabin dimensions of the AA-1. There were some additional benefits to this decision. It capitalised on the identification and reputation of the Yankee and its derivative, the AA-1A Trainer, and also resulted in a two thirds parts commonality between the designs, saving development time and production costs.

The new all-metal plane was powered by a 150-hp Lycoming O-320-E2G engine and could carry four people at 121 KTAS (224 km/h) in the cruise and was certified under US FAR Part 23 in 1971.

No sooner had production started than American Aviation was sold to Grumman and became Grumman American. Grumman continued production of the Traveler until 1975, making slight aerodynamic ‘clean-ups’ of the engine cowling and main landing fairings and increasing cruise speed on the 1975 model to 127 KTAS. Towards the end of 1975, production ceased after 834 Travelers had been built. The following year, the Traveler was superseded by the further refined AA-5A Cheetah.

Grumman’s engineers felt that the AA-5 design had more speed potential than the original Traveler, even with its 1975 improvements, and so embarked on a further aerodynamic clean-up and redesign. More changes were made to the engine cowling as well as the baffling to reduce cooling drag, the exhaust system was redesigned, the main landing gear fairings were improved, the ventral fin was removed, and the horizontal tail was enlarged to allow a larger centre of gravity range. Fuel capacity, too, was increased from the Traveler’s 37 US gallons to 52 gallons.

Introduced in 1976, the AA-5A Cheetah, still powered by the same 150-hp Lycoming, was another six knots faster than the 1975 Traveler.

Then in 1978, Grumman sold its light aircraft division to Gulfstream Aerospace and the division was renamed Gulfstream American. Gulfstream continued production of the AA-5A until 1979, by which time a total of 900 Cheetahs had been produced.

At the same time that Grumman engineers were redesigning the Traveler into the Cheetah, they were working on another variant of the AA-5 line – the AA-5B Tiger. The Tiger featured basically the same refinements as the Cheetah, but had a 180-hp Lycoming O-360-A4K bolted on the nose, resulting in a 139-knot cruise speed. Along with the greater power came an increase in gross weight, from the Traveler/Cheetah’s 2,200 lb (1,000 kg) to 2,400 lb (1,100 kg) on the Tiger.

As with the Cheetah, Gulfstream continued building the Tiger when they purchased Grumman’s American division, but in 1979 ceased production of all piston-engined aircraft. In just five years 1,323 Tigers had been delivered.

No Travelers nor Cheetahs have been built since 1979; however, American General Aviation and then Tiger Aircraft built the Tiger for a few years. Then, in 2007, True Flight acquired the bankrupt Tiger Aircraft and has since indicated that it wishes to restart production. The company is yet to produce any complete aircraft, although parts have been manufactured.

 

A WANDERING TRAVELER

I was first introduced to ZS-IXL, the Grumman American AA-5 Traveler we flew for this flight test and air to air shoot, back in 2013 when I was doing instrument training for my Night Rating. At the time it was in a fractional ownership with AFOS Flight School at Rand Airport, although it was only occasionally used for advanced training. Since then, two of the original owners, Dorrien Andrews of Flightsure and Kevin Reeves have assumed ownership along with Arthur Karatzas. The aircraft is still hangared at AFOS at Rand but if it wasn’t for the registration you wouldn’t recognise it.

In early 2017, IXL underwent a beautiful refurbishment, inside and out, at TAM and TAM Interiors at Wonderboom. Other than still being blue and white, it looks like a new aeroplane. It was completely resprayed in Flightsure colours, the seats were reupholstered in plush leather, a new windscreen and windows were fitted, and there is now a capable Garmin Aera 660 GPS mounted in the centre of the avionics panel. The engine still has around 1,200 hours until TBO, but the prop was overhauled and a new carburettor was fitted.

We called on the piloting skills of Jason Beamish for the air to air shoot and it turned out the plane also had a history with the Beamish family. Back in 1977, when IXL looked new, because it was, it was flying in the Defence Flying Club at Swartkops. Turns out, Jason’s grandad had given Jason’s dad, Larry, IF training on IXL. The morning’s flying was therefore a big reunion.

GETTING REACQUAINTED

Getting IXL out of the hangar necessitates using a nosewheel tow bar. That free-castoring nosewheel behaves a little like a shopping trolley wheel and is keen to swivel given the chance. The tow bar keeps it running straight. Taxiing, therefore, requires deft use of differential braking, and Kevin Reeves did caution us that the plane’s brakes are weak. “In terms of landing performance, treat IXL as if you’re flying an aeroplane without brakes,” he says. Does that mean we will be stomping on what little brakes we do have all the way to the runway threshold?

Once in the sun outside the hangar, IXL glistens. TAM’s refurb really has made the Traveler look better than new – from the front of the sparkling spinner to the oddly angular empennage. There are large strakes leading to both the vertical and horizontal stabilisers, as well as a strake on the underside. The AA-1 Yankee Clipper was a ‘hot’ little ship, and had a nasty stall, so these strakes presumably improve longitudinal and directional stability. This along with the AA-5’s longer wings tame the aircraft’s slow flight handling.

Another instantly noticeable feature of the Traveler is its smooth, flat finish. The AA-5, again thanks to its AA-1 Yankee Clipper heritage, shares the same unique bonded aluminium wing and honeycomb fuselage that almost eliminates the need for rivets without sacrificing strength. The big horn balances and large trim tab that runs the entire length of the elevator, suggest light control forces even with big deflections of the largish control surfaces at the rear of the plane.

Two 18.5 USG gallon tanks are in the inboard section of the wings, and there is easy access to the engine via ‘gull-wing’ doors latched down on either side of the cowling.

Although common, especially on NTCAs these days, the Traveler’s designers pioneered the use of a sliding bubble canopy on light GA aircraft – Pipers, Mooneys, Cessnas and Beechcraft all have doors above or below the wings. Thus, getting seated means hopping on the wing, sliding back the canopy and standing on IXL’s beautiful plush leather seats, before sliding your feet under the instrument panel. Climbing into the back seats requires a little more athleticism to get over the folded front seat backs, but once seated it’s roomy enough for two smallish adults. Impressively, the Traveler, with an empty weight of 1,271 lbs and max takeoff weight of 2,200 lbs, can lifts four average weighing adults of 80 kg, with the two 18.5 USG tanks topped off.

Like the front seats, the back rests of the rear seats also fold forward for access to the rear baggage compartment. With the seats down, there is more than two metres of space to work with – good for a bed, or golf clubs for the less adventurous.

Other than folding back rests, the seats stay put. You can’t move them forward or back, or up or down. That said, I was comfortable enough with the seats as they were, and there was space to spare, but I get the feeling the Traveler’s target market was trim.

The bubble canopy, with its fantastic visibility, makes the cockpit seem more spacious than it is. The seats are wonderfully comfortable, but shoulder room is snug. Neither Jason nor I are large, but we were shoulder to shoulder, and the head-on shots taken from the air to air shoot show us looking rather cosy. Also, tall people will have their heads up against the canopy, and you have to duck down when sliding the canopy closed to avoid being bumped on the head or knocking your headset skew. Nevertheless, the cockpit is comfortable enough for the three-hour legs you can safely fly with VFR reserves intact. And if you really want more headroom, you can fly with the canopy open.

IXL has a control wheel yoke, and the standard six-pack of primary instruments, plus a CDI, above which is mounted the touchscreen Garmin Aera 660 portable GPS – representative of new technology replacing old. Just off centre to the right of the Garmin is a standard Bendix King radio stack, and to the right of that, the engine temps and pressures. Along the bottom of the panel are mags, master, fuel pump and lighting switches. Engine controls are all of the plunger variety. From left to right: carb heat, throttle, a vernier mixture plunger, and primer. Below the throttle quadrant is the fuel selector. You can only select left or right, but the selector cleverly points at the fuel gauge for the selected tank. It’s a logical layout but isn’t seen on many planes – interestingly, despite the AA-5’s worse than average safety record, fuel related accidents are noticeably rare. In front of the right seat is a small ‘glove box’. Flaps are electrically operated with a switch between the seats – the amount of flap is eye-balled, as there are no defined stops – and behind the flap switch is the trim wheel. In sum, the cockpit layout is standard and logical.

 

FLYING IXL

With a few squirts from the primer, throttle cracked open, mixture rich and master on, the 150-hp Lycoming comes to life after a few turns and warms up at 1,000 RPM. Radio’s on and taxi clearance obtained, it was time to check out the brakes and that trolley nosewheel. This happened simultaneously. Turning requires some jabbing of the toe brakes but once the turn gets going, the Traveler can pivot on one wheel. To taxi straight, for the most part, you just hold in some right brake and increase power, and don’t let up until you’re at the holding point. It’s not surprising that common maintenance items are new brake pads. Power checks done, and with the plane configured for takeoff – one ‘notch’ of flap, or 10 degrees – it’s time to close the canopy, latch it, and line-up.

With the photo shoot already in the bag, Kevin and I were heading to the GF so that I could properly reacquaint myself with the Traveler’s manners. We were two up with half tanks on a pleasant Highveld mid-morning in March – about 24 degrees C and blue skies. That equates to about 400 lbs below gross with a density altitude of around 7,500 ft.

A little research showed that when things have gone wrong in AA-5 series aircraft, poor climb performance and landing overshoots have often been to blame. We were rolling up Rand’s 1,7 km long Runway 11, so we had plenty of runway and it was a good opportunity to put the writing to the test. Kevin says the trick to getting the Traveler into the air is to make sure the wings are flying properly before climbing out. This means rotating at 60 mph, allowing the mains to lift around 70 mph, holding the plane in ground effect until you have 90 mph on the clock and then raising the nose. Trying to climb out too soon will have you lumbering over the tree tops.

The rudder comes alive quickly, so there is only a short time when you have to use differential braking to keep the nose straight. We were airborne after about 500 metres and saw a steady climb out of around 800 ft per minute. Immediately IXL felt more spritely than the Cherokee 160 I had flown two weeks earlier and which I reckon is a good comparison. However, a little reading on the internet reveals that others have had the opposite impression of the Traveler’s climb performance.

At 7,000 ft, and in our case a density altitude of close on 9,000 ft, we flew with the throttle fully open which gave 2,500 RPM. Burning around 8 USG an hour, we were travelling at around 115 mph (100 kt) indicated. That works out to about 119 kt true, close enough to what the book says.

Memories from five years earlier instantly returned when I took the controls. IXL trims quickly and easily, and the controls are wonderfully crisp, light and responsive. The Traveler finds a pleasant balance between agility and stability. Pushing the aircraft into a slip, you run out of aileron before rudder, and the elevator authority lies somewhere in between.

With the throttle still fully open, the aircraft rolls smoothly into a steep turn and modest back pressure holds you in place. Leading with a bit of rudder keeps the nose on the horizon as you roll out and unload the wings.

Stalls have no ugly surprises. For a plane that is a bit sleeker and lighter in the hands than a Cherokee or 172, you’d expect to have to dab a little more on the rudder pedals to keep the wings level, and that’s all it requires. The tail can start to wag as the speed decays and the wings start to lose grip, but nothing happens suddenly, and after a gentle buffet the nose breaks cleanly ahead. With full flap this happens at around 55 mph (48 kt) and clean at 60 mph (52 kt).

Again, unlike the twitchy Yankee Clipper, the Traveler doesn’t sink like a brick. Conversely, it can be a bit of a floater if you come in too fast, and the small flaps aren’t all that effective. The Traveler is stable enough on the glideslope, but isn’t a rock-steady machine, so manhandling the controls can set up some rocking and rolling. 80 mph on final approach works well, but slow it down to around 70 mph across the fence. The nosewheel doesn’t like being planted down, so keep it up as the speed decays, being careful not to balloon, and you’ll be fine. Accurately ‘nailing’ the touchdown point takes a little practice, but the fibreglass main gear legs soak up landings nicely. Your only option is light braking, but we were comfortably stopped in 300 m on the uphill Runway 11 at Rand.

 

CONCLUSION

Taxiing back to the hangar, with that right toe brake gently reminding the nosewheel to go straight, I remembered why I had so enjoyed my early Night Rating training. I loved flying IXL. The controls are light and responsive, but docile enough to make the Traveler exactly what its name suggests – a tourer at heart, but with more inspiring handling than the competition. It won’t take a beating like the near indestructible Piper Cherokees or Cessna trainers, but it’s perfect for the family pilot who wants to drop the training wheels for something a little more spritely, without sacrificing simplicity and affordability.

Kevin and Dorrien say MPIs cost between R10,000 and R20,000 and IXL burns approximately 30 litres of avgas per hour. That’s around R500 an hour at current avgas prices. They both use the aircraft to commute for work around the country. And having a plane means a bit of fun too. IXL has competed in a number of President Trophy Air Races. They’ll be back again this year, so it will be interesting to see how it matches up to its 117 kt handicap.

 

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