First Flight - New Production Series 400 Twin Otter
Thread Starter
Originally Posted by Carrier
...there is one thing that puzzles me. I am wondering why you started this thread in the African Aviation forum instead of the Canada forum?
...well, I guess it's because I spent most of my flying career flying Twin Otters in Africa, and this forum is where most of my on-line friends hang out. That's probably not a very good reason, but it is the closest I can get to giving you a decent answer.Plus, of course, there are a lot of Twin Otters in use in Africa (not to mention a lot of Twin Otter pilots here in this forum)!
Michael
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There are still some legacy smaller production aircraft and far too many home-builts that carry fuel in the fuselage in close proximity to the human occupants. This is a safety hazard that has apparently caused unnecessary post crash fires and resulting deaths and injuries.
Years ago Cessna recognised the safety aspect of having aircraft fuel tanks located well away from the passenger accommodation. Most aircraft have fuel tanks in the wings but with some models Cessna even went beyond this, concentrating the fuel tanks in the outer part of the wing or in tip tanks.
The original DHC-6 Twin Otters carry fuel in belly tanks within the fuselage. Has the New Production Series 400 Twin Otter been redesigned to carry no fuel within the fuselage? If not, why not? If it does, then full credit for upgrading the design to meet current safety standards.
This raises the general question. Should aircraft designs being put back into production not be required to meet all current safety standards rather than perpetuating less safe legacy/grandfather standards? What do others think on this issue?
Years ago Cessna recognised the safety aspect of having aircraft fuel tanks located well away from the passenger accommodation. Most aircraft have fuel tanks in the wings but with some models Cessna even went beyond this, concentrating the fuel tanks in the outer part of the wing or in tip tanks.
The original DHC-6 Twin Otters carry fuel in belly tanks within the fuselage. Has the New Production Series 400 Twin Otter been redesigned to carry no fuel within the fuselage? If not, why not? If it does, then full credit for upgrading the design to meet current safety standards.
This raises the general question. Should aircraft designs being put back into production not be required to meet all current safety standards rather than perpetuating less safe legacy/grandfather standards? What do others think on this issue?
Thread Starter
Hi Carrier:
I can only offer you my personal opinion, which is that because the Twin Otter is a fixed gear aircraft - and one with very robust fixed gear at that - I think the risks arising from carrying fuel in the belly of the aircraft are pretty minimal.
If a single main gear leg collapses, the aircraft will pivot about the wingtip, the belly does not hit the ground if the wing is not deformed. If the wing does deform, well, any fuel that would have been carried in the wing would spill, thus negating the benefit of carrying fuel out there.
I appreciate your point that fuel carried in the belly could be a hazard in the event of a gear collapse or gear-up landing of a retractable gear aircraft, but I don't think much risk of that exists with the Twin Otter design.
I think the reason that most aircraft (that have wing fuel storage) put the fuel way out at the end of the wing has to do with reducing wing bending moment, not moving the fuel away from the passengers. If you purchase a Twin Otter with optional extended range wing fuel tanks, they are way out at the very end of the wing - in order to reduce the wing bending moment.
Michael
I can only offer you my personal opinion, which is that because the Twin Otter is a fixed gear aircraft - and one with very robust fixed gear at that - I think the risks arising from carrying fuel in the belly of the aircraft are pretty minimal.
If a single main gear leg collapses, the aircraft will pivot about the wingtip, the belly does not hit the ground if the wing is not deformed. If the wing does deform, well, any fuel that would have been carried in the wing would spill, thus negating the benefit of carrying fuel out there.
I appreciate your point that fuel carried in the belly could be a hazard in the event of a gear collapse or gear-up landing of a retractable gear aircraft, but I don't think much risk of that exists with the Twin Otter design.
I think the reason that most aircraft (that have wing fuel storage) put the fuel way out at the end of the wing has to do with reducing wing bending moment, not moving the fuel away from the passengers. If you purchase a Twin Otter with optional extended range wing fuel tanks, they are way out at the very end of the wing - in order to reduce the wing bending moment.
Michael
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What MM said. Never had a problem with the belly tanks myself and have never heard of it being a problem. In fact, for bush operations with primitive facilities, the tanks are ideally situated for ease of access and for a visual check before entering the aircraft.
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no
Very fancy airplane, but how come that with all that "intergalactic" and useless equipment for bush operation, the AUTOPILOT has NOT been yet certified.
without mentioning the fact that , the ANTI intuitive honeywell sistem doesn't allow you to have a quick situational awareness of all the user waypoints ( only one at a time is displayed on the map).
Don't get me wrong.. I love the twinotter ....but is there an avionics update in the near future, or we have to wait another 3 years ??
without mentioning the fact that , the ANTI intuitive honeywell sistem doesn't allow you to have a quick situational awareness of all the user waypoints ( only one at a time is displayed on the map).
Don't get me wrong.. I love the twinotter ....but is there an avionics update in the near future, or we have to wait another 3 years ??
