can t find something about use of WAI only with flaps up.comments about engine out climb penalty in case of WAI use on CLB ? by the time we raise the flaps, WAI can then be used as deicer
just found these limitations about B752.
On takeoff and landing, Wing Anti-ice should be OFF below 500 feet AAL to meet performance criteria. If an engine has failed, it must not be switched on until Flaps Up. These requirements are in order to achieve certificated climb gradients. For wing Anti-ice with inoperative engine only one Pack may be used.