Originally Posted by
gums
The thing about our HUD in the SLUF and Viper was it complemented the steam gauges.
Let's be pragmatic though, the primary reason HUD is considered essential in fighters (and is therefore cost-effective in all cases) is not because of the fact it can complement the primary instruments so much as the fact that
in a fighter you're going to have people shooting at you, and when that happens a split-second glance at the panel can mean the difference between life and death.
Someone mentioned that the PF could tell he was climbing by using the altimeter. My understanding is that "all" air data was unreliable except AoA...
As far as I know, altitude information was OK - certainly on the recorded instruments.
Remember that the engineering logic was designed around the idea that the failure of all three pitot tubes near-simultaneously was considered out-of-scope, and indeed it didn't happen until this particular model on this particular type encountered conditions with which they could not cope. The whole point of having the pitot and static information as separate "quorums" was so that the system would be able to determine where the failure was and disregard only that which was unreliable, and as such a failure of the pitots would not affect the static data and altitude data would have been OK at all times.
In any case the system was designed to preserve as much valid information as possible, with traditional pitch-and-power settings determined as contingency
and AoA ( separate probe) was deemed unreliable due to low airspeed.
Not until so late in the sequence that a recovery would have been difficult, if not impossible, and at that point the airspeed data was back.