问NSInvocation返回值，但使用EXC_BAD_ACCESS使应用程序崩溃

EN

for(NSString *key in [taxiPlanes allKeys])
{
        Plane *currentPlane = [taxiPlanes objectForKey:key];

        if(currentPlane.currentAction == nil)
        {
            NSString *selector = [[currentPlane planeTakeoffSequence] firstObject];
            currentPlane.currentAction = selector;

            // Calling for NSInvocation in [self ...]
            NSArray *action = [NSArray arrayWithArray:[self operationFromTakeoffAction:currentPlane.currentAction AtPoint:currentPlane.position]];

        NSLog(@"%@",action);
        }
 }

-(NSArray *) operationFromTakeoffAction:(NSString *) action AtPoint:(CGPoint) flightPoint
{
    NSMethodSignature *methodSignature = [FlightOperations instanceMethodSignatureForSelector:NSSelectorFromString(action)];
    NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:methodSignature];

    [invocation setTarget:fOps];
    [invocation setSelector:NSSelectorFromString(action)];
    [invocation setArgument:&flightPoint atIndex:2];

    NSArray *resultSet = [NSArray alloc]init];
    [invocation invoke];
    [invocation getReturnValue:&resultSet];

    return resultSet;
}