Fahrwerk1

The retractable undercarriages are designed modularly and thus can be adapted perfectly to different conditions. The undercarriages can be installed either firmly between two fuselage bulkheads or spring-loaded. If they are used together with FEMA solid tires, these retractable undercarriages withstand even extreme strains. The inflexible mounting between two bulkheads of the fuselage is perfect for standard models. It is advisable to use spring-loaded carriages for really soft touch-downs. The gas pressure spring makes the best possible damping even on the roughest runways. The damping can be adjusted to the weight of the model by three damping variations all of them available for immediate delivery. The required springiness of the gas pressure spring can be calculated as follows:

springiness (N)=model weight in kg x 40 (1kg~t10N) Gas pressure springs are available with a springiness of 200N, 300N, 400N. Models of more than 10kg require the attachment of 2 springs, more than 20kg require the attachment of three springs.

Stock number	A	B	C	D	E	F	weight*	model weight
9800A	272	80	68	140 - 165	66	92	680 g	12 - 25 kg
9810A	220	72	60	110 - 127	56	68	420 g	8 -16 kg
9820A	196	62	50	90 - 100	46	60	350 g	5 -10 kg
9830	172	54	44	70 -80	36	54	200 g	3 -7 kg

*without wheel, servo holder and bow

For the safety of your model, we recommend the attachment of a wheel brake independently of whether the undercarriage is attached firmly or spring-loaded. The wheel brake is operated by a servo and it can be applied extremely sensible though its high brake power. If the retractable undercarriage is attached firmly, the brake-servo can be mounted on the front fastening-bulkhead or directly on the chassis of the undercarriage.

If it is attached spring-loaded, the brake-servo has to be attached to the chassis of the undercarriage in order to ensure the safely functioning of the wheel brake when the retractable undercarriage is spring deflected. If the brake-servo is attached to the chassis of the undercarriage, an additional reversing lever (stock number 9890/22) is necessary.
We are looking forward to equipping your sail plane with a FEMA-retractable undercarriage. .

FEMA Modelltechnik Böhler GmbH Obere Rebbergstraße 11 D-77709 Wolfach Tel.07834/303 Fax 07834/47735 FemaModelltechnik@gmx.de