Requirements feasibilty and technical risk assessment


Another in the occasional series of posts on systems engineering, here’s a guide to evaluating technical risk, based on the degree of technical maturity of the solution.

The idea of using technical maturity as an analog for technical risk first appears (to my knowledge) in the 1983 Systems Engineering Management Guide produced by the Defense Systems Management College (1).

Using such analogs is not unusual in engineering, you usually find it practiced where measuring the actual parameter is too difficult. For example architects use floor area as an analog for cost during concept design because collecting detailed cost data at that point is not really feasible.

While you can introduce other analogs, such as complexity and interdependence, as a first pass assessment of inherent feasibility I’ve found that the basic question of ‘have we done this before’ to be a powerful one.


1. The 1983 edition is IMO the best of all the Guides with subsequent editions of the DSMC guide rather more ‘theoretic’ and not as useful, possibly because the 1983 edition was produced by Lockheed Martin Missile and Space Companies Systems Engineering Directorate. Or to put it another way it was produced by people who wrote about how they actually did their job… 🙂

2 responses to Requirements feasibilty and technical risk assessment


    This chart is similar to others in use today. But the probabilities seem out of line with what is actually in use – much low of a probability of occurance 1 in a 1E+5. Am I reading this right for a QL 5


      Matthew Squair 21/01/2013 at 8:14 am

      Hi Glen, apologies for the delay in responding but I was travelling in Siberia (really!) 🙂

      Yes the magnitudes are correct, that’s a logical consequence of scalling severity by factors of magnitude e.g. 10, 1000, 10,000 etc undere De Moivre’s definititon of risk. Most non safety related risk matrices conveniently ignore that logical entailment however…

      See the post Decision Theory and the risk Matrix