hawk37,
Yes, the 707 had a fixed (altho trimable) horizontal stab, with elevator.
The jackscrew that trimmed the stab had one rather undesirable problem...it was underdesigned, and could stall with heavy elevator inputs. This was not a problem in 'normal' flight, but was noticed when a few brave (foolish) crews climbed well above the optimum altitude (for the weight) and found themselves looking at a jet upset recovery.
One or two even chucked an engine off the pylon on the way down.
The L1011 does indeed have an all flying tail, but also has an elevator, that was linked to the stab for extra authority.
It was my normal practice to hand fly the aeroplane to altitude, as the control forces were delightful.
At M.865, no decernable mach trim inputs were noticed.
Having known quite a few of the Lockheed test flight guys later on, they mentioned that the mach trimmers fitted were really not necessary, but the FAA insisted, for certification.
Oddly enough, when the L1011 came onto the UK register, the Mmo was reduced to M.88 from the usual M.90.
Scarfed pitot at work perhaps...
TURIN,
Have flown some of the really older models, and don't remember any structural cracking in the area you mention.
Of course, I didn't look for any either, so you could indeed be correct.
Last edited by 411A; 25th May 2004 at 06:41.