Your questions don't pose any problems as long as you are curious and eager to learn abou,"How Stuffs work?",Trepid. Now lets go to the bird strike part. Yes,the plane can still manage to work.Commercial Air crafts are engineered with great care and all 4 engines won't go off at a time.Say for instance all the engines are off,the avionics won't work effectively due to the failure of hydraulic mechanism,but the emergency Hydraulics would let the plane move foreward provided it's on sufficient height. . In case all the engines fail,The pilots use RAT technology,ram air turbine to make the plane glide foreward and maintain it's height and that too at a speed range of 150 - 300 mph.See picture The RAT technology is powered by a generator that runs with fuel. Now the air craft can glide without any engine power. "Gliding" is a process where the aircraft can move forward in air without any engine power.They just whirl around a specific radius till they land safely. Now without the engine power,It's not possible to control the speed of the plane. The safe landing speed of Boing 707 is 170 mph.Without engines it's not possible to control the speed of such a huge machine and there are every chances that the plane may overshoot the runway after landing and crash.Therefore,the airport emergency does it's bit by flattening some of the tyres of the plane so that it's speed can be reduced and it doesn't overshoot the runway.The plane won't have sufficient power to takeoff again without engines. . There are instances where the pilot has made a passenger plane fly without engines for more than 120 Kms and still landed safely by the above proces but,it needs good pilots who can hold their cool. Now about communication,Pilots communication is not dependent on engine power.The cockpit's equipments and communication devices would run without engine power as they have special UPS(Unrestricted Power Supply) with battery banks.The ATC(Air traffic control will be in constant touch with pilot and captain) . I would love to talk on this topic more and more,Please ask if you didn't get any mechanism. The picture is of RAT.It's saves life after engine failure.