After watching a number of videos of air crash disasters, and the explanation of the crash through investigation of the black box data. How is it that the aircraft manufacturer cannot put small CCTV at various locations so that the pilot can see outside the plane? If there is a problem with no 3 engine which is on the tail fin, if they have a small camera on the top of the fuselage, the flight engineer can visually confirm from his monitor if a foreign object have struck the engine, or if there is a fire, and take the neccessary action.
From the cockpit, the pilot cannot see the flaps or the engines under the huge wings. So by putting some cameras below the fuselage, they can see the problem. Instead of relying on instruments that say oil pressure is falling, or that we are not getting a response from this part of the plane, the engineer can see the cause of the problem, like maybe, it hit something and the hydraulic fuel is leaking. Or that there is icing on the wings.
Maybe even equip the flight attendents with portable cameras that can transmit pictures to the cockpit, so that the pilots can be aware of potential problems inside the plane. These cameras can be kept at the crew station and if there is situation, they can record and transmit the information to the cockpit. Like maybe from the windows they can see that the engine is on fire, or the flaps have broken off, they can video it and transmit this to the flight engineer video screen.
A commercial plane costs millions of dollars and lawsuits from an aircrash will eventually cost them even more than the costs of the cameras.