Salute!
First the beacons:
- if they are using pulse code modulation or a variation of the spread spectrum technology, it's very easy to find the thing even with s/n approaching 1:1 Witness GPS with all the stuff basically on a single frequency. Same with your cellphones and such. You just have to know the "chip" sequence and rate.
Some of the RF gurus here can explain it better than I.
Second, about the pitch excursion theories:
- Doesn't take much to lose half your groundspeed in ten seconds if you are climbing at 10 or 15 degrees and not having motors going full grunt. Just a few degrees of flight path change at a reduced power setting will do the trick - think higher AoA and resulting increased drag.
If the air data went FUBAR and the jet thot it was going faster than it was actually going, I can see the thing climbing until reaching the AoA "protection". Unless the power was increased (unlikely}, a very rapid speed bleedoff would occur. The folks in the other incident being mentioned either took immediate action or the body rates were low enuff for the flight control system to counter the excursion (gotta find out more about that incident, but it sounds hairy). Not the "test flight" crash, but the two planes flying close together when one went yahoo.
- If you look at the jet I flew, we could reach 40 or 50 degrees AoA before the stability issue came to play. From then on we had little or no pitch authority commanding a nose down attitude or gee. Remember we were flying at a very rear C.G. So if we got real slow, real fast at a steep climb, then we didn't have enuff control authority to get the nose down. We "parked" and then started down at a great rate. Wasn't some violent "snap roll" or "nose slice" or "pitch up" ( also flew the VooDoo and it had the violent pitch up LOC). We couldn't enter the deep stall on purpose at pitch attitudes of 5 or 10 or 20 degrees without being real slow and with some harsh rolling or skidding commanded by the pilot.
So I can see entry to a stall or even a stall/spin if the jet started an extreme climb.
++++++++++++++++++++++
I feel most of us wish to discover the root cause of this accident, then come up with some procedures by the crew to mitigate the situation. If we have to change the flight control "laws" while we're at it, then so be it.
Contrary to popular belief, the Viper FBW system had several modes that changed the priority of the air data, body rate, AoA, and gee inputs. Nevertheless, the system was way less complicated and had zero inputs from the autopilot to bias the basic control laws - it acted as a very limited "pilot" command when seen by the computers. More on the autopilot later upon request, but it wasn't quad redundant and was basically a device to reduce workload while pulling out an approach chart or cruising along to and from the target.
later,
Gums sends...
-