Katana/Diamond question

[polar one]

I am not familiar with this aircraft at all, but a few years ago I was sticking my nose in one, and I seem to remember it has a temperature limitation(s) . If this is correct can someone post what they are..I am particularily interested in the plus side one.

Also, for anyone familiar with maintenance, how does the glass panel compare for maintenance and reliability in the training envirorment?

If there are any other operational limitations that are not typical of training aircraft, it would also be appreciated if you could post them

Thanks

[hairdo]

There is an airframe limitation of 55C on the C1 (don't know if there is for the A1). You don't have to start checking for that until the OAT is above 37C (if I remember right). But I gotta be honest with you, if you're flying in the DA20 above 30C, you'll probably sweat to death before the aircraft melts... it's a flying sauna! (good way to lose weight though)

[polar one]

Thanks Hairdo.

Can you clarify me though, what you mean by starting to check around 37 when the limitation is higher? Is the limitation based on something other than the ambient temperature?

You comments about cooling are noted. That was good to know as the plan is to operate in higher temps.

Thanks again

[MichaelP]

I've flown Katanas in Thailand where the temperature is often in the mid 30's and sometimes higher.
Yes it can get hot in there, but you have good ventilation from the side air vents and you can open the clear vison panels in the sides.
Someone wrote on here that the fresh air ventilation comes through the engine cowling. This is not true.

To me, anything over 30 degrees is hot and it doesn't matter what the number is.
Anything below -20 degrees is cold and likewise it doesn't matter the number.



Second point, glass cockpit.
In China we had some delamination of the G1000 glass panels, PFD and MFD. These had to be returned to Garmin for repair.
Otherwise, so far, touch wood, the G1000 system has been superbly reliable.

The Garmin 430 set up in our C1 has had problems.
We have lost use of the pilot side headset microphone through the Garmin intercom box and into the radio. No transmit!
The hand microphone uses the same pins, and so you lose both. I talked to Diamond about this as it is silly IMHO to not have the emergency backup the hand mike should provide.
Garmin simply said that is the way it is

[Tim]

as i recall the the temp limit isnt an issue for the aircraft that are white...dont have the afm on me though.

theres a little gauge in the cockpit, sorta like a carbon monoxide detector, that is in between the two seat backs on the back wall of the cockpit. it changes colour if the aircraft temp is too high.

[Aviatard]

The maximum takeoff temperature for the airframe is 131F or 55C. There is a caution for aircraft without white undersides that parking on a light colored surface in bright sunlight is not recommended at high OAT, however the temp limit applies to all aircraft.

The entry steps have a tendency to become weak over time and break off at the worst possible moment.

Students keying the starter again on a non-start before the prop has stopped will wreck the engine, due to the design of the starter and the gears being in the wet side. Metal in oil = throw that one away and get a new one.

Engine cooling on the ground can be a tricky one when the OAT is around freezing. There are two sets of removable baffles, and if you don't get them right you'll overtemp with a short period of ground idling.

Other than that, they're an all right little airplane, in my opinion.

[MichaelP]

We need to specify the aeroplane for some points:

Students keying the starter again on a non-start before the prop has stopped will wreck the engine, due to the design of the starter and the gears being in the wet side. Metal in oil = throw that one away and get a new one.

This is the Continental engine in the DA20-C1. All Continental small engines have this problem especially in the Cessna 150, 120, 140, and any aircraft with C85, C90, O-200, O-240, and IO-240 engines.
It's also a bad idea to touch the starter when the Rotax engine is running in the Katana, and the Lycoming in the DA40-180.

Engine cooling on the ground can be a tricky one when the OAT is around freezing. There are two sets of removable baffles, and if you don't get them right you'll overtemp with a short period of ground idling.

The baffles for the IO-240 engined C1 are supposed to be removed above 12.5 degrees C.
We used only the quick release front baffles on ours and leave the rear screw in baffles on the ground.
The cooling of the IO-240 is a difficult thing.
We've had too low temperatures on 20 degree C days with the baffles out, and too high with the baffles in!
We need to know if there is a temperature inversion on any particular day.
But in 20 degree temperatures, cruise climbing with the baffles in will keep the temps high green.
Without the baffles, we can never get the cylinderhead temperatures to go into the green, they are always below the green... Perhaps on a 30 degree day with no baffles the C1's temps will read where they should?

I'm thinking of buying a second hand C1 with a timed out IO-240 and putting a Rotax 912S with a constant speed propeller in it... End of all the problems with old technology engines.

Oh and the hot cockpit...
The P51 Mustang has the same hot cockpit problem, and then there's a hot Merlin up front as well.
I assume that many on this forum would rather fly a Cessna 172 than a Mustang for the same reason.

[Invertago]

The P51 Mustang has the same hot cockpit problem, and then there's a hot Merlin up front as well.
I assume that many on this forum would rather fly a Cessna 172 than a Mustang for the same reason.

Actually I keep my ol Mustang in my hanger because tail draggers are dangerous ... but that's another story. Katana's are nice, fast and newer, but if you're over 6'0 like me, and it is a hot day outside, you'd probably rather do a 8 hr cross country in a good ol 172 rather then 7 hours in a Katana. Can't really compare them on the basis of training myself though, as I've only flown a diamond on long trips. Did love the view though!

The other side of the coin, just as metal never forgets past abuse, I'd be a little concerned about an old katana having had a little too much sun exposure in its past.

[Hedley]

many on this forum would rather fly a Cessna 172 than a Mustang

Having flown both, I hate to mention it, but the P-51D
was something of a disappointment. Don't get me wrong,
with that skinny wing it was fast as hell - we went everywhere
at 250 knots, the maximum speed at low altitude - but it was
insanely, painfully loud, guaranteed to piss off the neighbours.

Remember all the lawsuits that the fighter combat people had in
St Catharines, with just two little Extras? I think they ended up
getting kicked off the field.

Plus, the P-51 wasn't very much fun to fly. The flight
controls became enormously heavy at speed, and quite
disappointingly, it bled airspeed off horribly when you
tried to pull a little G. I like pulling G. The P-51D did
not.

And, it's a maintenance hog. I suspect you're going
to spin wrenches on it for at least 10 hours for every
1 hours of flight. And the real ratio might even be
worse than that.

Grass is always greener. Don't get me wrong, I think
everyone should fly a P-51D at least once, but if someone
gave me one, I'd immediately list it in Trade-A-Plane. Like
being married to a supermodel, the overhead and tantrums
would crush most mortal men.

You want a monoplane, that's great fun to fly? Get an MX2.

[MichaelP]

I never thought I'd read Hedley intimating he'd rather fly a Cessna 172

[hairdo]

Thanks Hairdo.

Can you clarify me though, what you mean by starting to check around 37 when the limitation is higher? Is the limitation based on something other than the ambient temperature?

You comments about cooling are noted. That was good to know as the plan is to operate in higher temps.

Thanks again

It's the airframe that has a temperature limitation. As Tim mentioned, it's between the a/c seats, to let you know if the airframe temps get above 55C. We start to look by the time we get an ambient temp of around 37C or more (which thankfully doesn't happen too much). Again, as mentioned by Tim, I think it's mostly a concern for DA20's that are not white, but both are equally affected if the indicator changes color (no flying for you).

As far as cockpit cooling goes, it's not too bad once you're airborne with a bit of speed as you can then get some airflow from the vents. The worst point for cooling is on the ground as there is little airflow in the cockpit, so if you have to hold short for a while... That said, I understand that Diamond in London, ON taxi around with the canopy open in the summer time. However, I would confirm that with Diamond. It's just more of an issue with flight training if a student goes solo and they forget to latch the canopy down properly prior to takeoff. They might get a little more cooling than expected.

Other than that, they're a good training aircraft.

[Thunderstrike]

That said, I understand that Diamond in London, ON taxi around with the canopy open in the summer time.

I personally have never seen this take place. I also find it highly unlikely for two reasons.

1 - The canopy on a C1 acts like big parachute. If it's unlatched it can even blow open on a windy day. I imagine with a prop turning up front the canopy will either be subject to immense strain and eventually break off and/or drop the plane on its tail.

2 - Someone will eventually forget to latch it properly. I for one don't want to see what happens to a C1 when the canopy pops open at speed....that would get really ugly.

[hairdo]

That said, I understand that Diamond in London, ON taxi around with the canopy open in the summer time.

I personally have never seen this take place. I also find it highly unlikely for two reasons.

1 - The canopy on a C1 acts like big parachute. If it's unlatched it can even blow open on a windy day. I imagine with a prop turning up front the canopy will either be subject to immense strain and eventually break off and/or drop the plane on its tail.

2 - Someone will eventually forget to latch it properly. I for one don't want to see what happens to a C1 when the canopy pops open at speed....that would get really ugly.

Like I also mentioned, you'd have to check with Diamond to see if that's acceptable to taxi with it open. I don't recall if there's anything in the AFM that mentions this, so again you'd have to check with Diamond before trying this. However, I don't think you would find there to be all that much strain on that aircraft at low power settings on the ground and I find it unlikely that it would push the tail to the ground since the canopy is located fairly close to the main gear (vertically speaking) and it requires 100lbs of force on the tail to push it down (when you push at the tail).

However, I completely agree with #2 and that's more likely the reason it's not done.

[Thunderstrike]

That said, I understand that Diamond in London, ON taxi around with the canopy open in the summer time.

I personally have never seen this take place. I also find it highly unlikely for two reasons.

1 - The canopy on a C1 acts like big parachute. If it's unlatched it can even blow open on a windy day. I imagine with a prop turning up front the canopy will either be subject to immense strain and eventually break off and/or drop the plane on its tail.

2 - Someone will eventually forget to latch it properly. I for one don't want to see what happens to a C1 when the canopy pops open at speed....that would get really ugly.

Like I also mentioned, you'd have to check with Diamond to see if that's acceptable to taxi with it open. I don't recall if there's anything in the AFM that mentions this, so again you'd have to check with Diamond before trying this. However, I don't think you would find there to be all that much strain on that aircraft at low power settings on the ground and I find it unlikely that it would push the tail to the ground since the canopy is located fairly close to the main gear (vertically speaking) and it requires 100lbs of force on the tail to push it down (when you push at the tail).

However, I completely agree with #2 and that's more likely the reason it's not done.

Hmm. I suppose it just feels less sturdy in the actual plane.

100 Pounds though? It certainly doesn't feel like that much....or maybe I just don't know my own strength

[hairdo]

100 Pounds though? It certainly doesn't feel like that much....or maybe I just don't know my own strength

It's a rough estimate, but I've seen some lighter people push (or try to) the tail down and they had considerable difficulty. And it's more of how much weight you can put down on the aircraft than how much strength...

[MichaelP]

Again you need to specify the aeroplane.
Our small 100lb or less lady instructor easily lowers the tail of a Katana.
When we had the snows, I found the Katana sitting with its tail on the ground and the DA20-C1 sitting on all three wheels, with still a little force required to drop the tail. Its the difference between a big heavy lump of Briggs and Stratton technology on the front and the lightweight efficient Rotax.

Personally I find it easy to push the aeroplane backwards while carefully steering the castoring nosewheel.

As for taxying with the canopy open... someone did it once and I immediately put the kibosh on it.... By all means an instructor can lift it a little and hold on tight to it for taxying, but not for runup!
The DA40 has a second open position for the front canopy latch to allow ventilation on the ground.