Cats
There was a specific programme of stress testing carried out on a Viking airframe at Swanton Morley as part of the entry into service - 1 airframe was sacrificed on a test jig/rig.
What the outcome was I am unsure but this cyclic testing led to the introduction of 27000 launches life. Since I would suggest that an average Viking probably does no more than 500 launches a year - we're probably only approx. halfway to that figure..................
Note that comparing a K21 and Grob 103 is not 'apples with apples' as the design and construction methods are very different. Therefore the fatigue life will be different.
Finally I am unaware that the Viking is operating overweight. I've not seen that documented anywhere. Since they are military aircraft the BGA dispensation is irrelevant anyway (even though the aircraft do have BGA numbers !). Actually some of the aircraft differ radically in weight (empty) as they have had various repairs and various schemes applied. It should be noted that the ones based at coastal airfields weigh more than those based more inland by a fair few kilos so apply a blanket comment about overweight is a bit broad brush !!
Note that it's 33 months now since the pause..........................and counting
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