Structural failure

[cfiatzph]

How do 170's standup as far as structural integrity? What is likely in any airplane to come apart? The tail first? The wings? What are the weaknesses on the 170? Have there been any come apart? Just curious there seems to be a lack of ADs for the airframe which indicates that it probably has a robust airframe.

[4stripes]

The 170 is the basis of the 172. Over 42,000 172's were made, proving the structure is a sound design.
The main weakness in any airplane is the nut behind the wheel.
Most 170's have been damaged through mishandling during the take-off and landing phases.
Structurally, the seat rails have always been a real weakness. When they wear, the seat doesn't always lock properly. The steep body angle of the 170 amplifies the problem when the seat decides to unlock and slide aft (usually during take-off). The pilot is unable to reach the rudder pedals causing loss of directional control. Proper maintenance, and always verifing that your seat is "locked" will minimize this weakness.

[dacker]

One point to remember about our airplanes... they are all over 50 years old. While this is a testament to their ruggedness, they are no longer new and are subject (just like all airplanes) to the effects of corrosion and fatigue. Hang around a maintenance shop for a little while and you will see a lot of airplanes that are discovered to have serious corrosion. This does not happen over night, meaning that they are often flown for quiet awhile before the problems are discovered.
Factor out corrosion and fatigue and I believe that it can safely be said that these airplanes (and the 172s) are very sound structurally. I believe that I read in an AOPA review a couple of years ago that the 172 had never had an in-flight break up, not counting flying into thunder storms.
David

[Curtis Brown]

Buy the Safe-T-locks and use them on the seat rail to lock your position. They are cheap insurance!

[cessna170bdriver]

How do 170's standup as far as structural integrity? What is likely in any airplane to come apart? The tail first? The wings? What are the weaknesses on the 170? Have there been any come apart? Just curious there seems to be a lack of ADs for the airframe which indicates that it probably has a robust airframe.

I've never heard of an in-flight structural failure of any 170, but I haven't really searched the databases to confirm. Like dacker says though, the youngest of these airplanes are 50 years old and we probably don't need to be out doing 4-G maneuvers with them every day.

Miles