DHC-6 Questions:
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Everything has its price!
I remember the grand kerfuffle when I wanted a cigar lighter socket in a Twotter. Not to smoke cigars but just to run my noise-cancelling headset, one of the early ones that didn't have a battery pack. There I was thinking to just find a source of juice and tap into it like some bush man. Wrong! You needed technical approval and blah-blah-blah... (Meanwhile, for all you Cessna drivers out there that company got a new anti-smoking chief exec who did away with same on his products, obviously not thinking of other things you could power off a cigar lighter!)
Here you already have the bog-standard PT6 starter-generator approved and in place. If you wanted to go for more amperes I guess that would mean finding a new, more powerful starter-generator and getting that certified. Then you would have a problem with spares, some aircraft with the old kit and one or two with the new kit and how do you get your overhauled unit when it's a one-off and you are out back of nowhere and, "Oh, look, they sent us an old model starter-generator instead of the new model," or vice-versa...
I already saw a Chief Pilot staring a hole in the mahogany bar counter after some bright spark had sent us a PT6-28 instead of a -27 because it's thermally adequate, not thinking about that funny gizmo on the nose case that only the Twotter has. (Of course the old engine had been flown to time-ex on Friday afternoon for a quick engine change on the weekend to be back in service on Monday.) I slithered up next to this unfortunate to ask, "So, Pat... Heard any good PT6 jokes lately?" when he did rather exhibit signs of a serious sense of humour failure there, yes.
I think much of the appeal of the Twotter is in its rugged simplicity (who would buy it for its looks, a blind man?) and any upgrades have to detract from that.
Here you already have the bog-standard PT6 starter-generator approved and in place. If you wanted to go for more amperes I guess that would mean finding a new, more powerful starter-generator and getting that certified. Then you would have a problem with spares, some aircraft with the old kit and one or two with the new kit and how do you get your overhauled unit when it's a one-off and you are out back of nowhere and, "Oh, look, they sent us an old model starter-generator instead of the new model," or vice-versa...
I already saw a Chief Pilot staring a hole in the mahogany bar counter after some bright spark had sent us a PT6-28 instead of a -27 because it's thermally adequate, not thinking about that funny gizmo on the nose case that only the Twotter has. (Of course the old engine had been flown to time-ex on Friday afternoon for a quick engine change on the weekend to be back in service on Monday.) I slithered up next to this unfortunate to ask, "So, Pat... Heard any good PT6 jokes lately?" when he did rather exhibit signs of a serious sense of humour failure there, yes.
I think much of the appeal of the Twotter is in its rugged simplicity (who would buy it for its looks, a blind man?) and any upgrades have to detract from that.
Originally Posted by Chuks
...I wanted a cigar lighter socket in a Twotter.
But... we have provided two 14 volt convenience outlets as standard equipment on every Series 400 Twin Otter. One is located on each side of the center pedestal - about beside where the radar screen used to go on the legacy aircraft.
14 Volt Outlets
They are provided to charge up your phone (or whatever). You won't need them to power a noise cancelling headset, because two David Clark noise cancelling headsets, permanently hardwired to and powered from the aircraft, are also provided as standard equipment. But, I suppose if you really want to use your own personal noise-cancelling headset (and not the ones that are basic to the aircraft), you could power it from these outlets.
Michael
Originally Posted by Chuks
...not thinking about that funny gizmo on the nose case that only the Twotter has...
Michael
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Yeah, that one!
If you were a cruel person then you would laugh at the sight of those guys unwrapping their freshly-overhauled PT6 and then freaking out because... no beta back-up valve! I am and I did, of course!
So this first airplane, is it being delivered with the uprated engines or bog-standard -27s for, uh, commonality? A little bird landed on my shoulder, you see...
Also, could some perverted nicotine fiend stick a cigar lighter into that "utility socket" and then use it to light a cigarette, or would that void the factory warranty?
So this first airplane, is it being delivered with the uprated engines or bog-standard -27s for, uh, commonality? A little bird landed on my shoulder, you see...
Also, could some perverted nicotine fiend stick a cigar lighter into that "utility socket" and then use it to light a cigarette, or would that void the factory warranty?
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Chuks....
We don't need "technical approval". We don't care about warranties and we don't need Approved Data, Supplemental Type Certificate or anything from the FAA. We have our own engineering.
...and yes, I have your inquiry bookmarked for future reference.
...and yes, I have your inquiry bookmarked for future reference.
Last edited by Spadhampton; 8th May 2010 at 23:47.
Originally Posted by Spadhampton
...We are forced to wear the David Clark headset?
We elected to provide the two noise-cancelling headsets as standard equipment on every plane for occupational health and safety reasons. The flight compartment of a Twin Otter can be quite noisy at takeoff power, and the superior noise attenuation of these headsets (combined with the noise cancelling capability) protects the pilots from exposure to excessive sound pressure levels.
Originally Posted by Spadhampton
...We don't need "technical approval". We don't care about warranties and we don't need Approved Data, Supplemental Type Certificate or anything from the FAA. We have our own engineering.
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The first 25 years are difficult...
After that your head has been reshaped to fit the David Clark headset, sort of like those Flathead Indians but in a slightly different way.
I now have the latest David Clark, the X-11. It is very light and comfortable, if not quite as gee-whiz as the Bose. When you are a clumsy person who works in difficult environments (heat, dust, humidity) then a rugged headset is a good thing and I always found David Clarks to be tough. The latest one seems to have kept the virtues while also being much more comfortable.
I wear custom-fit earplugs along with my headset, something I should have started with a long time ago, with hindsight. Nowadays the wife asks, "Aren't you going to answer the phone?" when I can only reply, "Phone?" Aaah, DeHavilland!
Must be the Mexican Police. "Engineering approval? We are the Mexican Police. We don' need no steenking Engineering Approval!"
I now have the latest David Clark, the X-11. It is very light and comfortable, if not quite as gee-whiz as the Bose. When you are a clumsy person who works in difficult environments (heat, dust, humidity) then a rugged headset is a good thing and I always found David Clarks to be tough. The latest one seems to have kept the virtues while also being much more comfortable.
I wear custom-fit earplugs along with my headset, something I should have started with a long time ago, with hindsight. Nowadays the wife asks, "Aren't you going to answer the phone?" when I can only reply, "Phone?" Aaah, DeHavilland!
Must be the Mexican Police. "Engineering approval? We are the Mexican Police. We don' need no steenking Engineering Approval!"
Originally Posted by chuks
...I now have the latest David Clark, the X-11. It is very light and comfortable...
I've used this headset for all the hours I have flown the Series 400, and I'm quite happy with it. We have invited about a dozen pilots from the industry to fly the Series 400 as part of our human factors evaluation, and no-one has had anything to say about the headset, other than commenting that it is nice to have a noise-cancelling headset provided as standard equipment.
Michael
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Do you still need to press the intercom button to talk to each other? I laughed at myself one day, having a conversation with my cojo whilst shut down and without headset on the ground. I discovered I was still pressing the intercom button everytime I said something. Doh!
I guess thats what 120hrs plus per month in the plane does!
I guess thats what 120hrs plus per month in the plane does!
I know exactly how you feel...
The intercom on the Series 400 Twin Otter is voice activated. I was pretty sceptical about this idea when I heard that this was the way that the Honeywell KMA-29 audio panel worked, but after having flown the aircraft for a few hundred hours, I am very happy with it.
The electronics behind the voice activated intercom are very fast. The intercom activates right away when you speak, and there is no clipping of the first or last words of what you say. I was a bit concerned that the intercom might activate when not wanted during (for example) takeoff, but it doesn't do that. In fact, it doesn't even activate if you open the window, unless you start to speak.
The rocker switch on the control yoke only moves in one direction, that is from the center to the 'radio transmit' position. It's blocked from moving in the other direction, which means that after a few days in the plane, you get used to not pushing it automatically when you want to speak to the other pilot.
It's particularly nice for the right-seater to have the voice-activated intercom during busy times, for example, when reducing power just after takeoff, etc.
Michael
The intercom on the Series 400 Twin Otter is voice activated. I was pretty sceptical about this idea when I heard that this was the way that the Honeywell KMA-29 audio panel worked, but after having flown the aircraft for a few hundred hours, I am very happy with it.
The electronics behind the voice activated intercom are very fast. The intercom activates right away when you speak, and there is no clipping of the first or last words of what you say. I was a bit concerned that the intercom might activate when not wanted during (for example) takeoff, but it doesn't do that. In fact, it doesn't even activate if you open the window, unless you start to speak.
The rocker switch on the control yoke only moves in one direction, that is from the center to the 'radio transmit' position. It's blocked from moving in the other direction, which means that after a few days in the plane, you get used to not pushing it automatically when you want to speak to the other pilot.
It's particularly nice for the right-seater to have the voice-activated intercom during busy times, for example, when reducing power just after takeoff, etc.
Michael
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In anycase.........
I doubt very seriously that anybody will decide whether or not to order a new -400 based on the headset type. Sales rhetoric can sometimes paint an invincible picture of product. Every David Clark I ever put on was uncomfortable after an hour or so. I don't have to wear them anymore so I digress.
The Series 400 will be appended to the existing type certificate for the preceding versions (1, 100, 110, 200, 210, 300, 310, 320) of DHC-6 aircraft.
Certification is not my speciality, but to the best of my knowledge, the 400 follows substantially the same cert basis as the 300, except in areas where the aircraft has been modified (for example, the new avionics), in which case the prevailing (most current) certification criteria is applied.
There are some areas in which Viking has voluntarily upgraded the aircraft to a more contemporary cert basis that what is required.
Hope this provides more clarity than confusion...
Certification is not my speciality, but to the best of my knowledge, the 400 follows substantially the same cert basis as the 300, except in areas where the aircraft has been modified (for example, the new avionics), in which case the prevailing (most current) certification criteria is applied.
There are some areas in which Viking has voluntarily upgraded the aircraft to a more contemporary cert basis that what is required.
Hope this provides more clarity than confusion...
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A sticky question...
What is that old thing, CAR3? You have some really grey areas in that, stuff that just wouldn't be allowed today, so that I doubt it would be economically doable to recerify this machine to the latest standards. There is nothing wrong with that; have a look at what Boeing do with the 737, for instance.
When you get involved with the DC-3, is that ever another world. That thing doesn't even have stall breaker strips and I had Mr Training Captain Ironbutt McHardass telling me that "You young guys (I guess I was only 32 then) don't know how to do a full-breaking stall but show me whatever you can..."
Just a short time later there we were looking at all green in the left front windscreen and all blue in the right front windscreen as we were ploughing out of the sky over the Florida Glades with lots of down and not much forwards, full right aileron but not a lot of change happening in my lousy little life. "So this is why they put stall breaker strips on modern airplanes!" was most of what was going through my tiny mind. No telling what was going through his but the rest of the ride was much quieter! Then you have its ergonomics, from before that word was even thought of, and it shows!
Sit there staring at your new glass panel and be happy, is all I can tell you!
When you get involved with the DC-3, is that ever another world. That thing doesn't even have stall breaker strips and I had Mr Training Captain Ironbutt McHardass telling me that "You young guys (I guess I was only 32 then) don't know how to do a full-breaking stall but show me whatever you can..."
Just a short time later there we were looking at all green in the left front windscreen and all blue in the right front windscreen as we were ploughing out of the sky over the Florida Glades with lots of down and not much forwards, full right aileron but not a lot of change happening in my lousy little life. "So this is why they put stall breaker strips on modern airplanes!" was most of what was going through my tiny mind. No telling what was going through his but the rest of the ride was much quieter! Then you have its ergonomics, from before that word was even thought of, and it shows!
Sit there staring at your new glass panel and be happy, is all I can tell you!
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Vyse, 80kt, Vx=87
Hi Mike M
I quite think u r gonna X the Atlatic with the latest of the fleet soon...
Coming back to the initial thread:
I agree that instead of 80kt, Flaps 10, id go 87+flaps 0 to clear obstacles... as I only see 1 and only Vx under DH certif/AFM/etc manuals. Am I wrong?
Moreover, 80kt is Vyse @ 12500lb, so the correct reply should be Vyse for Flaps 10 (ie 80-4/1000lb lighter than MTOW) and best RoC (SE+Flaps10 config). Computed accordingly. Wrong again?
Even you, V1..., I d be surprised if you can confirm 80kt being best angle with flaps10° and BOTH engine at MCT?
Your lights on this being very welcome!
Thx
I quite think u r gonna X the Atlatic with the latest of the fleet soon...
Coming back to the initial thread:
I agree that instead of 80kt, Flaps 10, id go 87+flaps 0 to clear obstacles... as I only see 1 and only Vx under DH certif/AFM/etc manuals. Am I wrong?
Moreover, 80kt is Vyse @ 12500lb, so the correct reply should be Vyse for Flaps 10 (ie 80-4/1000lb lighter than MTOW) and best RoC (SE+Flaps10 config). Computed accordingly. Wrong again?
Even you, V1..., I d be surprised if you can confirm 80kt being best angle with flaps10° and BOTH engine at MCT?
Your lights on this being very welcome!
Thx