Zodiac CH 601 XL

The Zodiac CH 601 XL is the fast development stage of the Zodiac line, which traces back to Chris Heintz's CH 600 that first flew in 1984. Two German type data sheets apply: 61196 lists the "CH-601XL" series with Czech Aircraft Works s.r.o. in Staré Město as the manufacturer until production ended on 31 December 2006, while 61196.1 names Zenair Ltd. at Huronia Airport in Ontario from 1 January 2007. Both data sheets name Zenair Ltd. as manufacturer and type custodian. They only ever list the "CH 601 XL" series – the widely used "XL-B" label is not a separate German type approval. It is common in the market, but what it means on an individual aircraft has to be established from documented installation.

The XL is an all-metal aluminium low-wing aircraft with a cruciform tail, fixed tricycle gear and two side-by-side seats in a 1.12 m wide cabin. With an 8.20 m span and 12.3 m² of wing area, the German ultralight approval permits 472.5 kg maximum takeoff weight with a rescue system installed. Power comes from the Rotax 912 S/ULS/ULSFR rated at 100 hp, driving one of five approved three-blade ground-adjustable composite propellers. Fuel sits in two 45-litre aluminium wing tanks, or optionally 36-litre tanks; a BRS parachute is fitted behind or ahead of the firewall.

The Czech-built version's flight manual quotes a 6.1 m/s sea-level climb rate with the Rotax 912 ULS and Woodcomp propeller, roughly 100 m ground roll on tarmac and 190 km/h IAS cruise at 3,000 ft and 5,500 rpm. Throttled back to 4,500–5,000 rpm consumption drops to 12–15 l/h, for which the manual quotes 850 to 924 km – but to dry tanks with no reserve at all, so plan on roughly 100 km less. German ultralight limits are tighter than the manual figures: VNE 224 km/h CAS, manoeuvring speed 146 km/h, flap limit 130 km/h and a minimum speed of 63 km/h CAS. Demonstrated crosswind is only 5 m/s.

Its strengths are genuine cross-country speed for a metal ultralight, long range, a riveted structure that is straightforward to repair, and the series' international spread. The weaknesses deserve equal billing: in April 2009 the NTSB counted six in-flight structural breakups on the 601 and 601 XL since 2006. The Netherlands grounded the CH 601 XLs registered there on 24 October 2008; on 7 November 2009 the FAA issued a Special Airworthiness Information Bulletin, and AMD and Zenith Aircraft issued the retrofit requirement the same day. The retrofit package reinforces load-bearing structural parts of the wing and controls; the exact scope is defined in the safety alert documentation. Registering a serial number requires written confirmation from type custodian Zenair – under data sheet 61196 for serial numbers up to 1 January 2007, and under 61196.1 for all serial numbers with no date limit. Add a narrow cabin, modest demonstrated crosswind and a low flap speed.

The CH 601 XL suits pilots who want fast touring on an ultralight budget and are comfortable with a riveted metal airframe. When buying, proof of the retrofit package comes first: a sticker alone is not enough. What matters is documented installation, the correct current edition of the type data sheet, the written Zenair confirmation for the serial number, and a recent weighing report – the data sheet states empty weight only "per weighing report".