Originally Posted by
Feathers McGraw
OK, something weird about the blade angles then, it makes them look different in that embedded picture.
First let's clear this up. This pic is definitely showing four blades.Any concern about the angles maybe related the fact that the props are all feathered.
With 2500 hours on Hercs albeit a long time ago, the one thing I do remember is that if you lost the Utility hydraulic system, you were in for a world of hurt. You lose wing flaps, main landing gear extension, NWS, and half the flight controls. The other half were looked after by the Booster hydraulic system and I think you could use the Aux hydraulic system (which operated the ramp and door ) as an emergency NLG extension. It's been a while. But I do know that we never wanted to lose the Utility hydraulics and were always scan checking fluid levels and pressure. My bet is these guys lost Utility system hydraulics probably as soon as they attempted to lower flaps (since they landed flapless).
Interesting post event gear config ie NLG and right main up, while the left looks fully extended. If they did indeed loose the Utility system then they most definitely had problems with the gear. You can manually wind each main landing gear down. It takes a long time and its bloody hard. However, once you break free of the top and get it moving , the gear will often then begin to free fall. Had to do this once in slightly different circumstance where the left main gear wouldn't budge despite having hydraulics. You can imagine me jumping up and down and slamming my boot onto the the manual gear extension crank handle in desperation until all of sudden it went bang and the gear dropped like a stone and locked down. Do not get in the way of that crank when this is happening!
There are inspection windows to check the gear is locked down although it's tight if you got cargo in there. If you don't get a lock down then your next move is to open all four inspection windows and wrap 25,000 lb chains (standard fare on a C-130) around the struts on both sides and join in the middle with a chain tensioner. Several chains required (6 on each pair of struts I think) and quite a bit of time and messing about. Now I'm not sure of the mechanics here but this chaining procedure 'ties' the struts on either side together to the wheel bay and prevents the gear (in most cases) from collapsing on touch down.
Now I don't have speakers so couldn't hear the ATC audio so I'm not sure if they had a fuel issue and couldn't hold until everything was sorted, but 'm guessing they got both mains down but only the left locked down. Maybe due to cargo they couldn't access the inspection widows or get chains around the right main struts so landed (for whatever reason) with the right main not locked down. I don't know why they didn't try to lower the NLG with the Aux hydraulic system (you can hand pump it if you have a failed pump or electrics), but they wouldn't have had any NWS anyhow so it may have been a conscious decision to leave the NLG up.
So I am guessing that apart from being fast over the fence, the touchdown went well until the right main gear collapsed causing the aircraft to slide off to the right of runway. Then the wing tip struck the ground and ripped off the outer wing and plylon fuel tank which then resulted in a ground loop.
Until we hear something we won't know what if any of this happened on the actual flight but flapless is most likely loss of Utility system pressure and in my experience the rest of what follows is just a bad day in the office at the end of a very long flight. Any way, well done the crew for walking away from this.
Here's The Utility hydraulic system reservoir and associated piping situated on the left main gear forward bulkhead. Notice the site glass for checking fluid level.Its had one or two knocks by the look of it!!
