DG Flugzeugbau DG-1000 Flight Manual page 57

Flight manual DG-1000T
4.5.7.2 Fin water ballast tank
For optimal thermalling performance and handling water ballast in the fin tank
should be used to compensate the forward movement of C.G. due to the mass of
the wing water ballast. Please refer to section 6.8.6.
Warning: It is prohibited to use the fin tank in icing conditions see sect. 2.18.
Warning: If there is the risk of freezing, dump all water before you reach
freezing altitude, latest at +2°C (36°F), or descend to lower altitudes.
If you suspect a tank is leaking, dump all water immediately.
Water ballast raises the approach speed, so it is recommended to dump the
waterballast before landing. Dump the ballast before an outlanding in any case.
4.5.7.3 Filling the waterballast
See sections 4.2.2 and 0.1.1. After filling level the wings and check if the dump
valves are tight. It is not allowed to fly with leaking watertanks as this may
result in an asymmetric loading condition.
4.5.7.4 Dumping of the waterballast
First open the fin tank, then open both wing ballast tanks together. Do not empty
one wing tank after the other to avoid an asymmetric loading condition.
Warning: If the fin ballast dump valve handle can be operated with unusually
low effort (force of the retaining spring is no more apparent) you must suspect
that the fin ballast can't be dumped any more. In such case don't dump the wing
ballast to avoid an unsafe backward C.G. position.
4.5.7.5 Valves leaking, servicing
Please refer to the maintenance manual sect. 1.8 and 4.1.
Issued: July 2005 EASA app.
4.19