Oh come on now, you are comparing apples to oranges. Houses don't fly, and neither do most cars. Furthermore, both are designed to allow humans to be inside of them. That statement is so irrevelent that I will address it no further.

On the subject of crashes 'caused by radio/ servo failure by experts': apparently you have witnessed far more than I have. I, like another suggested, have witnessed crashes which were blamed on 'interferenece/ component failure', but in most cases: I have my doubts.

Case in point: I witnessed a giant scale FW-190 crash at the 2008 Mint Julep event. I later heard the pilot blamed interferrence. My opinion tho was different: the pilot was completing a figure 8 during exteme crosswinds and was nearing (or over) the pits/ flightline. I saw the plane banked nearly 90 deg, attempting to complete the turn and get it back over the runway, when it suddenly spun in. My impression: hi speed stall/ excessive angle of attack. IF the aircraft had any reduntant sytems, I'm thinking they would have made the aircraft heavier, and thus more difficult to turn.

Just my opinion, but I did not see any crashes that weekend that could be attributed to radio and/ or servo problems. And until now, I have never heard of a shorted servo, or it's wiring. But then again: I have no experience with giant scale aircraft, so maybe the components of such large aircraft are more prone to such things? Both of my servo failures resulted in servos that would not move. They did not cause an excessive current draw, and all other servos and Rx remained fully functional.

One more thing: I DID have one of my Hangar 9 Hellcat 'shot down' be someone turning on a Tx at a very large event which had no impound and poor frequency control. I KNOW it was another TX being turned on becuase the mechanical landing gear ( 1 servo per 'leg' ) suddenly started to come down just as the aircraft abruptly rolled left and into the ground.
Of other possible causes:
1) battery failure of any type, including shorted servo: the landing gear would have remained in the up position.
2) pilot error and/ or windshear/ exteme weather: the landing gear would have remained in the up position.
3) retract switch was inadvertantly switched while simultaneuosly left thumb developed severe cramp, causing it to contract toward my hand: retracts switch is located away from active hand and thumbs, must make very deliberate effort to switch it.

I don't think having system redundency would have helped, UNLESS I had another pilot controlling another TX, but even then..................I'm not sure it would have helped.

I have since converted all of my expensive ($200 ~ $1500) aircraft to 2.4 GHz systems (with dual/ reduntant Rx antenna)