Plastic Flying

PlasticFlying moved to www.plasticpilot.net

2007-08-28T13:53:00.001-07:00

Dear reader,

given its succes, and to make things easier to manage, but also easier to read for you, this blog has been moved to http://www.plasticpilot.net/blog

I'm sorry if this cause any inconvenience to you, but hope to see you there soon !

PlasticPilot

G1000, ADF, DME and dual ILS display

2007-08-26T04:02:00.001-07:00

The topic of ADF and DME integration in the G1000 seems to be a source of misunderstanding, so I will try to make the situation a bit more clear for anybody.

At first, you must know that ADF and DME are not part of the standard G1000, but are options. One bad consequence of this is the way they are integrated. At audio box level, there are keys for turning their audio on or off, but all the rest goes through soft-keys and the FMS knobs.

Typically, tuning and ADF frequency needs the following steps:
1) Press the ADF / DME softkey
2) Go in the frequency box
3) Change the frequency with the FMS knobs
4) Press enter to validate the new frequency
5) Press enter to activate the new frequency (flip-flop)
6) If needed, use the FMS knobs to adjust the audio volume

Not exactly simple, isn'it ?

The same kind of procedure is needed to switch DME from NAV1 to NAV2 receivers. Because of this, the school where I trained decided to always fly with the DME coupled to NAV1, to avoid too complex and lengthy manipulation in flight.

Something else that is not possible with the G1000 is to have two simultaneous display of the ILS. I know many people tuning NAV1 and NAV2 on the ILS while flying with classical instrumentation, so as to be able to continue in case of receiver failure during the approach. As the G1000 has only one HSI, this is not possible. Nevertheless, you can tune the ILS on the two NAV boxes, and in one fail it is possible to switch the HSI source with one soft-key click.

DA 50 update

2007-08-22T23:16:00.001-07:00

Diamond air recently posted more information about the DA50 SuperStar on their website, it is even possible to reserve one ! I won't recopy all of the information here, but I just want to highlight some points.

Unlike the DA40 and DA42, the DA50 will have a dual G1000, with two PFDs and one central MFD. This is possible because Diamond moved the circuits breakers on the ceiling.

The engine will be a 350 HP turbo continental, controlled by a FADEC. The prop is not yet defined, and could be 3 or 4 blades. It won't be pressurized, but offers built-in oxygen, and TKS de-icing as well as a parachute are optional.

They announce a speed of 200+ kts in the low flight levels, which seems credible, depending the definition of "low", but the PA46 familly has the same performance, with pressurization.

DA50 is a five seater, but Diamond call it 4+1, as the 5th seat is between the two normal back-seats, which is the way the automtive industry is doing for years, so one more time Diamond re-use automotive ideas.

Begin a modern aircraft, the DA50 will include some goodies, like an MP3 player, and other gadgets.

AOPA: Technologically Advanced Aircrafts safer !

2007-08-08T05:19:00.001-07:00

In a recent report, the AOPA Safety Foundation (ASF) examined statistically the kind and rates of accicents of Technologically Advanced Aircrafts (TAA), and compared them to the rest of the General Aviation fleet.

This report is available online, and I strongly recommend to any TAA interested pilot to study it. It highlights many interesting factors. The TAA appears to be safer, but the kind of accidents occuring the mosts are different from classical aircrafts.

One typical factor is that TAA have more weather related accidents than classically equiped aicrafts. This is quite surprising given all the weather infos that modern MFD can display. I guess (and this is a personal opinion) that because weather is depicted with more detail, pilots are more inclined to put themselves in challenging situations than with low information.

Once in a critical weather however, even the best MFD won't help you getting out of it. At most, it will tell the pilots that he is in crazy weather where he should never even think of going.

Before you jump in and read this report don't forget one thing. The total time flown by TAA's is still ridiculously low compared to the rest of the fleet, so it is not sure now that the trends shown will be stable or confirmed over time.

It is neverthelss a very interesting piece of information, and again I advise any TAA interested pilot to read it.

IFR in IMC in a DA40 with G1000

2007-08-07T07:26:00.000-07:00

IFR is about two things: flying according to procedures, and being able to maintain the plane attitude using instruments only. Procedures can be trained in simulator and in flight. Simulator and simulated IMC can give a base for flying in clouds, but nothing is like the real thing. When I made my G1000 training on a DA40, and then my IR(A) renewal, I did not had the opportunity to fly actual IMC.

I returned to Cannes Aviation recently, for some pleasure flying in south-eastern France. While in cruise a flight level 90, I flew through a perfect IPL (IMC practice layer). It was a stratus layer, approximately 800 feet thick, exactly centered on my flight level. I remained in that layer for about 20 minutes, having my first actual IMC with a DA40 / G1000.

After a few minutes using autopilot to get re-used to IMC, and practice my scanning, I disconnected the AP and flew manually. The first feeling was a strong nose down attitude, which was purely resulting from disorientation. The huge sky / earh line on the PFD confirmed that I still was flying straight and level.

Scanning the G1000 is really easy, because any attitude change is made obvious by the PFD. The slightiest roll movement results in the screenwide horizon line moving, and this is immediately noticeable. In pitch, the scale is quite wide as well, so any change is easy to detect. Flying in clouds with an accuracy of +/- 20 feet was really easy, even with the very sensitive wing of the DA40.

As a conclusion, the G1000 held all its promises when dealing with the hardest aviavion task, single pilot IFR in IMC.

New Cirrus fun

2007-07-30T02:42:00.001-07:00

CirrusDesign annouced on the 23rd of July the extension of their product line with the SRS (SR-Sport). This new aircraft will fit in the FAA new category of Light Sport Aircraft (LSA). Note that there is nothing equivalent to that under JARs...

Basically this will be a light aircraft, with modern engine (single lever), and avionics, limited to 120kts because of its LSA certification. It will include many of the other Cirrus typical features, including the chute.

Someting I like about it is that it will have removable wings, and it will be possible to have it in a trailer ! I always thought that the gliders guys I frequently see on the motorway are lucky to have their planes with. If this becomes possible with a powered plane, it could be deadly attractive. Just drive to your holliday spot, and then have fun arround ! This also removes the risk of jeopardizing the hollidays if flying to the spot is not possible !

So that's one more plane I put on my "to-be-flown" list, if anyone get's one, let me know !

More info from Cirrus in their press release.

A new plastic engine

2007-07-27T03:45:00.000-07:00

Diamond Aircraft recently announced together with a german / austrian company called MBtech the test of a new diesel engine in a DA40. This new engine develops 170hp, whereas the currently used Thielert engine develops 135hp.

This could result in serious improvements of the DA40 performance, if this engine is selected. We must now watch Diamond Aircraft, as several options are possible now, especially as Thielert decided to stop production of their 1.7 liters TDI engine in favor of the new 2.0 liters version.

I would like a personnal note here about Diamond CEO, Christian Dries. This guy is not only running Diamond, but also doing all of their maiden flights (DA50 maiden flight link), together with the managing test pilot Sören Pedersen.

This says a lot about the company spirit by Diamond, and I personally like it. It is not just one more MBA holder (with all respect that MBA holders deserve) running it just as any other company...

Side-slips in Cessna 172 with a Thielert 135 engine

2007-07-25T12:55:00.000-07:00

My previous post about the side-slips being prohibited in C172 with Thielert 135 engine started a debate in comments, so I checked everything again today, and here is what the AFM and my flying club decided.

The risk of non-coordinated flight is such a plane fuel starvation. As the diesel engine needs very high fuel pressure (about 3'000 bars), it has a low pressure and high pressure pumps. If the pumps run for more than 15 seconds without being fed, they will get damaged.

As prolongated side slips (15 seconds or more, which is a very long side-slip) can lead to such a starvation if the tanks contain less than 1/4 of their capacity, the AFM discourage side-slips when fuel quantity is below 1/4 in the tank on the outside of the slip, if it is the selected one.

As a conservative measure, my flying club did prohibit all side slips. This has been done after a bad experience by a member, doing a long side-slip to show someting to a passenger, not to manage and approach. After 13 seconds, he experienced a serious loss of power, which could be shown in the logfiles of the plane when examined by Thielert.

I don't want to draw a conclusion here, and I'm obviously open to comments.

C172 TDI cockpit retrofit

2007-07-16T12:49:00.000-07:00

During a recent flight with a C172 retrofited with a Thielert 135 TDI engine, my passenger was kind enough to make some inflight photos of the cockpit, so you can show how it looks after the diesel adaptation.

My apologies to the photo gods, this is not exactly a great luminosity balance, contrast, and whatsoever, but it shows what it has to.

The first big change is obviously the AED / CED displays, positionned each side of the control column. The one to the left is partial on this plane, as there are no fuel quantity gauges, this plane still uses the original ones.

You can see on the left indicator that the engine is burning 7.3 USG / H of Jet A1, and the right side one indicates that the prop is turning at 2280 RPM, and that the engine is developping 96 percent of its power.

All parameters are in the green, but if it was not so, some LEDs would be orange or red. As you can see, even in this visibility, the LEDs are easy to read, which is true under any light conditions, as far as I can say after more than 50 hours of flight using such indicators.

Other changes to this vintage Cessna cockpit can be noticed on the left side, below the fuel gauges. Here is a new panel with some lights, for low fuel, glow, AED and CED alerts. On the top row are also two buttons: the left one is for the FADEC test, and the rightmost one is to acknowledge any caution / warning.

In posts about FADEC operation I mentionned an "Engine Master" switch. On this plane, it is the big gray switch just below the electrical master, in the bottom left corner of the picture. To avoid any misuse, it is the kind of switch that must be pulled to operate.

The final change to the cockpit (except for the single lever, not shown here, but hey, it's only a lever), is the switch to force FADEC B to be active. It is under the red cap, just left of the hand microphone.

Liberty XL2 test flight

2007-07-11T12:24:00.000-07:00

After a long period of inactivity, I revive this blog today as I was given the opportunity to test-flight a Liberty XL2. This plane falls in the plastic category by its engine, an AVGAS injected engine controlled by a FADEC. Nothing else is plastic in the model I tested.

There is much to say about the liberty, but all can be summarized in one point: this plane seems to be desinged to be cheap. This plane is clearly done to fly. This sounds good, but the problem is that it is NOT made to roll. Taxi, take-off and landing rolls are hard times.

A lot has already been said about the finger braking system, so I will be short on that. The nosewheel is free of rotation, so guidance during taxi and at low speed is done using brakes, which are controlled by two levers beside the power lever (don't say throttle, it's a FADEC engine).

The free nosewheel system also exists on the DA40, but it is somehow restricted, whereas the Liberty nosewheel is totally free. Even moving it arround with the towbar is not obvious.

The engine operation is as simple as a FADEC makes it, single lever, and a fuel pump that has an automatic mode. The suprising thing is that the pump is then controlled by the fuel pressure, so when throttle goes back to IDLE, typically on final, the pump starts, and it's quite noisy. When idling, the engine sounds really unhappy, so it's very tempting to taxi with more than IDLE, but this results in excessive speed.

Engine check is quick and easy thanks to FADEC, but a remark here is that the breaks locking system does now allow for holding the plane immobile during power check, and I had to manually operate the breaks at this time.

Two other strange features appear at before take-off checks time. The flaps are electrically operated with three LED to indicate their position. These LEDs are really not bright enough, so it's hard to see them from left seat.

The second oddity is about the elevator trim. It is electrically operated as well, and I must say electric only. There is no trim wheel in the cockpit. I personally dislike it, because in case of failure of the servo-trim, you are left with nothing but a plane potentially out of trim and no way to correct it.

The side visibility when at holding point is not exactly great, and its hard to check that no one comes on final before you line-up. And as you might guess, the line-up is not easy because of the brakes.

I tested it on a grass runway, and I must say that the take-off roll was just horrible. Directional control is not as problematic as during taxi as the rudder becomes operative quickly. Nevertheless I would not have to handle a rejected take-off with the finger brakes.

Anyway, what made that take-off roll unpleasant is the absence of dampers. We felt each and every bump in the grass, and I never bounced that much before take-off. I'm even wondering if this is not kind of business development for chiropracticians. Add on top of that a relatively small cockpit, and it was quite hard to fit my 1m96 in.

Things got better once in flight. The forward visibility is quite good, and as the wings are short, side visibility is good as well. The central stick is quite comfortable in hand, and the plane is responsive. Climb performance is not exceptional, but acceptable.

Flaps retraction is quite long, and as there is no position preselection, it is necessary to press the button for long seconds. Once in cruise, the indicated airspeed went up to 120kts.

We flew some steep turns, at 45° and 60° bank with no noticeable things to report. Climbs and descent are ok. Using Vy, with half fuel, we obtained sustainable climb rates of about 800 - 900fpm in clean configuration.

Approach is easy, flaps make speed control easy, and the plane behaves very well on final. The touchdown was really firm and bouncy. The directional control of ground roll was also really problematic. The goal clearly is to land and control it with rudder, and touch down slow enough to not need any braking.

As a general conclusion, this plane is made to fly, but not to taxi or go through ground rolls. The toe-brakes option is definetily a must, and a more controlled nose-wheel would be good. Better dampers would make it much better, but this is not an option.

Some plastic news...

2007-06-20T03:25:00.000-07:00

First, the Diamond Superstar (DA50) is progressing quickly through its test flight program. This is a high performance single engine, which was shown for the first time at the last Diamond Christmas party, and flown for the first time last spring, by Diamond CEO himself (and a test pilot).

The definitive diesel engine is not selected yet, could be Thielert, but SMA is still in the competition. The new thing is that there could be a pressurised version of this high performance single engine... making it quite appealing. The last pressurised single engine I know are the Piper Malibu series, and the P210 from Cessna, both quite old design...

Something else pleased me recently, while reading a paper about the Cessna Citation Mustang very light jet... its avionics is nothing else than... a G1000. So once I'll have found the money, the transition should not be that hard ;-)

Plastic projects

2007-05-15T11:08:00.000-07:00

I stopped posting last days, mostly because I think I went quite arround the topic, given my present experience.

My plastic projects for the time being include the plastic challenge, which is to fly plastic engines only for 2007. Obviously any new plastic opportunity would be good, like flying an avidyne cockpit, or a Cirrus or Columbia aircraft. I don't mention the DJet, but who knows...

This blog is still open for comments, and any news about topics left open (as the gelcoat issue, or the DA42 incident) will lead to new postings.

Plastic Evangelism Hard Time

2007-05-12T13:22:00.000-07:00

Some friends / fellow pilots / readers call me "Plastic Evangelist" or "Diesel Evangelist", because of my well known enthusiasm for plastic flying. I fully agree with them and I assume this nickname.

However the downside of it is that each time a plastic plane has a problem, some come back to me, with a big smile, pointing out that these plastic technologies are dangerous, can not be used in aviation, etc...

Anyway, as a good "evangelist", I never change my mind nor to change their, but I always repeat the same info, re-state the same arguments, endlessly.

The strange point is that most of time, the people criticizing plastic planes are the same that years ago criticized GPS. I think of a particular friend of mine that flies IFR, and learned it before GPS. He is really good and safe at it, no point here. When GNS430 came in the game, he just used it as a NAV/COM. He was not really against it, but he just did not wanted to make the effort of the change.

However as more and more RNAV only waypoints pop arround, he started to reluctantly use the GPS part, and slowly converted to full GPS use.

My point here is that plastic technologies are still considered as "new", and each incident will be pinpointed... and if you're a plastic fan as I am, you should always keep in mind that the change going on is coming from true technological, operational and economical trends, and the safety aspects are also important, so this change will continue, it's only a question of time.

Who reminds the time where IFR was without RNAV ? Amongst those of you who drive manual shifting cars, who reminds the time of "double clutch" ? I'm sure where cars were introduced, many people objected that they had sooooo inconvenient compared to horses...

Only time will tell... don't be tough to non-convinced people.

Plastic Evangelist

Plastic Engine Cessna 172

2007-05-11T08:50:00.000-07:00

You're getting bored of DA40 planes ? Lucky you, I will now post about a C172 in which a plastic engine has been retrofied. Unfortunately for my own experience, it has classical instruments, and is VFR only. I think you need to know that I converted to C172 by the very end of last year, and I never flown a classical engine C172 before (except as PAX...).

Nothing special in engine handling compared to the DA40, as it's the same powerplant, same FADECs, and nearly same AED / CED. On this particular Cessna, the fuel quantity indicators are still the old gages, they are not integrated in the new indicators. One noticeable difference in engine management compared to DA40 is the cool down time. After landing, you have to run on IDLE power for two minutes with a DA40, whereas you can stop the C172 immediately. This is probably due to the much larger air intakes in the C172.

For C172 classical engine pilots, a new issue will raise: fuel management. I'm sure you all manage fuel properly in terms of quantity, but with the diesel you have to care about balance as well, because the new fuel system does not have a "both" position for its fuel selector, so you'll have to switch tanks periodically. If you fail doing so, you riks a fuel imbalance, but also temperature problems.

The particular C172 I fly now had the long range tanks options, but the tanks have been reduced with the plastic engine retrofit. They have now a capacity of 20 USG each, so an autonomy of about 6h40... Should be enough for most operations.

When comparing the performance graph, it seems that the diesel version is slightly less performant below 5000ft, but then the turbo advantage makes the difference. On a normal day, I could once climb from 1'5'00 ft to 13'000 ft in less than 25 nautical miles.

One important restriction concerns the TDI engine bad reaction to fuel starvation. The high pressure pump can be damaged it if runs witouht fuel for more than 15 seconds. As a consequence of that, long out of balance situation could lead to severe engine damage. I know at least one case of pilot who loss engine power during a long side-slip. The club management answered to this issue by prohibiting side slips...

DA40 differences training (JAR)

2007-05-09T11:40:00.000-07:00

This post presents what you can expect from a DA40 (plastic engine) differences training under JAA rules. I talk here of a DA40, with classical instruments, not G1000.

The theory part will focus on diesel operations, but that's easy, and on electrical system, which is of paramount importance when a plastic engine is part of the game (see my post about the DA42 double engine failure...).

Then comes the practical flight. As I already told, the DA40 is really a forgiving plane, thanks to its good wing desing. You will go through various but all uneventful stalls, and manoeuvers like steep turns.

As always, you will have the landings practice then. Normal, engine off, and so on. Some changes here about the fuel and FADEC system. The typical drill for engine failure is:

1) Maintain speed (as always)
2) Try force FADEC B
3) Activate fuel transfer in case you pumped all of the main tank

If you've enough altitude, you can try an engine restart, but before doing so you have to switch engine master to OFF and back to ON, to activate the glow plug for pre-heating.

Depending on the lift / drag ratio of the plane you flew before, your first landings can be really floooooooooaaaaaaaaty. Remind to come with the correct speed, corresponding to your weight, and you'll land ok.

The final stage of your differences training should include flapless landings. This is because the flaps are electrically driven, so JAR make that mandatory (quite smart on this topic...). As you can imagine, flapless landing in a floaty plane is not exactly the easiest part of the training.

In my very particular case, the differences trainig took 4h03 of block time, including a solo nav of 30 minutes, and dual flight to another airport than base which were needed because I was checked-out by the new club at the same time. The exercices part took something like 2h45.

DA42 double and simultaneous engine failure after take-off

2007-05-08T01:01:00.000-07:00

Here is a quoted text following the belly landing of a DA42 after a double and simultaneous engine failure.

"Twinstar take-off crash divides Diamond and ThielertDiamond Aircraft Industries and Thielert Aircraft Engines are at loggerheads over the cause of a double engine failure involving a DA42 Twinstar during take-off in Germany last month. The incident, in Speyer, south-west Germany, is being probed by the Germany air accident investigation bureau, but the cause of the engine failure is known to be the effect of a transient drop in the electrical voltage to the two engine control units, Diamond confirms. The European Aviation Safety Agency has ordered the companies to find a swift solution, and Diamond's chief executive Christian Dries says his company is seeking EASA certification to install a small back-up battery for each engine's control unit. When the crew of the accident DA42 arrived at the aircraft (D-GOAL) they found it had a flat battery and started up the engines using an external power unit. This deviated from the published operating procedure, which only allows one engine to be started with an external power unit - the second has to be started using aircraft-generated power. Just after rotation, as the landing gear was retracted, the aircraft experienced simultaneous engine failures on both TAE Centurion 1.7 diesel engines, forcing the crew to make a belly landing in a field adjacent to the runway. Diamond says that retracting the gear placed a load on the electrical supply from the engine-driven alternators that caused a temporary voltage drop that could not be covered by the flat battery, and the accident has shown the engine control unit to be intolerant of transient electrical fluctuations. TAE says the problem is an airframe issue, adding that being forced to issue an airworthiness directive for the 1.7, which is set to power other aircraft types, would have a huge impact on its business. Diamond dismisses these claims and argues the control unit supplied by TAE should have been able to accept a 50 millisecond transient, but it started to reset after 1.7 milliseconds, and during the engine control unit reset the propeller system sensed the power loss and auto-feathered. Meanwhile, Diamond has issued a service information bulletin that clarifies standard operating procedures. Dries says the question remains: who is to pay for the fix?"

I don't want to blame or finger-point anyone. The german investigation bureau will establish the facts. My only personnal feeling (and it is not more than that) is that taking-of in a plastic engine plane immediately after a known battery problem is arguable.

Any update will be published here.

UPDATE: new information and a service buletin are discussed on http://www.plasticpilot.net/blog/2007/09/03/da42-double-engine-failure-service-bulletin-published/

DA40 - Cabin interior and wings plus pictures

2007-05-07T11:51:00.000-07:00

One other thing in DA40 that makes it match my criterions for a modern aircraft is the ease of access, and cabin layout. All of those who flew a PA28 with passengers on the backseat know what it is about... DA40 access for front seats an back seats is easy, specially because a rear side-door is available.

One noticeable thing is that the front seats can not be adjusted, as they are integral part of the fuselage. The stick is part of the seat, and the rudder pedals can be adjusted. There's not too much space in the cabin compared with a PA32 or Bonanza. Diamond did however put a lot of effort on designing the back seats. As already mentionned, they are easy to access, and there is enough space for two adults (w&b permitting), but the most enjoyable thing is that the back seats are sligthly higher tha the front row seats, so the passengers can have a decent forward view. To convince yourself, sit down in a PA28 / 32, and then in a DA40. You will have no doubts which is better as a PAX.

Now, regarding the wings. As I said in previous post, the wingspan is ENORMOUS, for a total of 12 meters (close to 36 feet), leading to a high glide ratio, and low wing loading. An other interesting thing is that flaps are very wide, but not so deep, as ailerons. You can see that on the next picture.

You can also constat the the wingtip has a mini winglet. On DA42, the winglet is huge, close to 50cm high. The new version (DA40 XL) also has a larger winglet.

As I'm in my photo library, I can not resist to the pleasure of giving you a photo of one of the famous local mountain, known as Cervin or Matterhorn. Picture from FL130.

Comment and answer

2007-05-06T13:54:00.000-07:00

I had this interesting comment as an answer to the "Trust the FADEC... but monitor it"

"Hi, yesterday a plane crashed into a bay in Flensburg - north Germany, and 4 people died. If the press ist right it was the DA40 with the Thielert-Diesel from a sports clup in Flensburg. So I googled the word "blackbox" because the press said "the blackbox was found" and i hadn't heard of blackboxes in single piston planes before. It is disturbing to hear from you, that the powersetting of the FEDEC seems to have a mind on it's own. Just speculating: What if you do sightseeing - slightly slow and low and heavy - and the powersetting changes just a bit - while you are talking to passengers - would you realize the loss of speed early enough?"

So my three answers to that. First all my sympathy goes to the familly and friends of all the people touched by this tragedy.

As an attentive pilot, you will notice any power change by noise change. I fly with a Bose X headset (thanks Santa...), but I still feel any power change, except may be very slight one, but such changes won't have impact. Even if you don't notice it, you will loose speed, and the stall warning will manifest itself quite early (see the previous post), and the stick will become less strong, and this should help you to notice the approach to stall.

Second part is that low and slow is never a good combination, so it depends how you define them. Anyway JAR OPS requires a minimum of 500ft AGL (more over crowded areas), and despite its nice stall characteristics, flying close to stall speed is never a good idea. This kind of problems can happen with any engine, be it FADEC equipped or not. You could have to manage a capricious mag, a fuel line problem leading to starvation, or fuel contamination on any plane. If you want time to react or more time to find a landing spot, slow and low is not a good option.

If your passengers want to see a particular spot (let me gues... their house ?) just circle it instead of flying slow.

Thanks for the comment anyway, they're always welcome.

DA40 - Aerodynamics

2007-05-06T13:33:00.000-07:00

This post is the first of a series about the DA40, partly about the plastic technology, but more generally.

What is noticeable with the DA40, but also other plastic planes (Cirrus, Columbia, ...) is that they are a brand new generation of planes, designed from scratch, taking full advantage of plastic. This has impact on how wings are designed, but this is also a product of modern computer aided design tool.

One my preferred characteristics about the DA40 is its stall characterstics, which make a stall kind of a non-event. Let me be clear here. I don't say that you can't stall a DA40, if someone design once a non-stallable plane, I would be really interested ;-)

What makes the DA40 stall good and safe is that stalling it does not induce any drop, be it wing or nose. The plane just falls (about 1300 fpm / 40 kts). Compared to nose drop common to PA28 or C172, it is even more uneventful. My basic training took place on a plane that lost at least 700ft in wing / nose drop at any stall.

A part from the pelasant way of stalling, feeling safe and smooth to the pilot, the factor that make it s safe plane is that the risk of spin is really low, as no drop occurs. And given the ENOURMOUS wingspan of DA40, the ailerons maintain efficiency at very low speed.

On the back side, ENORMOUS wingspan leads to a very low wing loading (weight per square meter / feet of lift generating surface) makes it really reactive to turbulence. Any wind speed change, or thermal lift will have strong effect, so flying precisely requires a quick reaction time.

The second consequence of low wing loading is that it glides really well, but precise landing is not easy. Depending on weight at landing, speed can be adjusted from 58 to 70 kts on final, and beleive me, adjusting is important. Approach with 5 extra knots, and you will have a long flare, which can be critical on runways shorter than 800 meters (2400 ft).

Another strange thing is the stall warning, which from my point of view sounds too early. If the wind is slightly turbulent on take-off, it is quite common to have a "stall-warning check" immediately after take-off. I don't feel it good to have a stall warning horning arround 65 when the plane can fly at 45. May be next versions could include a flap dependent stall warning, however as the stall warning is not electrical but pneumatic, it's not so easy.

G1000 Nav setting / beacon identification

2007-05-05T08:31:00.000-07:00

This post addresses a topic that is more IFR oriented, but can also affect VFR pilots using radionavigation.

As all IFR navigation is based on radar vectors or radionavigation, it is of paramount importance to properly tune the nav receivers, and the corresponding indicators.

The routine I used on planes with classical intrumentation was:

Nav 1 - Frequency - Course selector - Ident - DME coupling - RMI coupling
(same for nav 2)
ADF frequency - Ident - RMI coupling

The G1000 includes two nav receivers and an optional ADF receiver. In terms of indicators, there is an HSI which also includes two RMI pointers, as seen on the picture below:

This indicator is really flexible and powerful, may be too flexible in fact.

The HSI needle can be coupled to NAV1 / NAV2 or GPS. Each pointer can also be coupled to a NAV, GPS or ADF. When you've to fly a complex procedure needing more than one or two navs, you can define a setting that matches it, but then tuning the G1000 and then interpreting it is not obvious.

The school where I trained had a standard setting which was:

Primary NAV or GPS on the HSI, NAV2 on le single line pointer, ADF on the dual line pointer. One desing remark here to M. Garmin: on classical instruments, the single line pointers are green, and the dual line pointers are yellow. On the G1000, they are both cyan.

Having a standard setting help you to easily interpret your pointers, and to resist the deadly tempation to spend too much time during an approach to build up a specific setting. It could seem restrictive, but in fact it helps remaining proficient.

Another important topic is the identification of beacons, by identification of morse code. The G1000 includes a morse decoder, so when you tune a nav frequency, it will "listen" to the code, and display it. This value is not comming from the database, so it can legally replace the identification by a human. But unfortunately, this feature is not available for ADF and DME.

More on DA40 specifics in the next post.

G1000 transition tips

2007-05-03T11:27:00.000-07:00

Here again, what I can tell is how I made it, which worked quite well, but there is no absolute / universal way to manage this transition, which is not obvious as it could seem.

One first advice is that if possible, you should to your G1000 transition on a plane type you already know, so you can truely focus on the G1000 only.

The first step is to do some theory training, either on your own or withing a school with an instructor. I took such a one day course, but I prepared myself by self-studying before. Material for this includes the User Manual and Cockpit Guide published by Garmin (available on www.garmin.com). Be careful when choosing your download. As the G1000 includes engine parameters display, there are variants of the documents to match each plane type.

Garmin also created a software simulator running on PC. Not on all PCs, by far not as only a few video chipsets are supported. Unfortunately, this simulator is only delivered to people actually buying a G1000, and it is not available for download. Nevertheless, as some clubs did buy such planes, they put it on the internet for their members... Using the google searchbox on top of this page, you should be able to find it easily, especially if you look for Norwegian aeroclubs...

If you can run it, this is a good tool, but as there is no throttle / AP like in the GNS430 simulator, its use is a bit more complex. The help file is definetly worth a good look.

The next step is to consult some books or CD / DVD / web training tools. I personally used the one from Max Trescott, which can be found on www.glasscockpitbooks.com. It is quite good, even if the procedure part addresses only the US way of flying (please remind I'm a Swissie...).

Once you will feel ok with the G1000 theory, you can envisage some practice. For the first few hours, an FNPT-II is really the good tool. If you fly on MEP, you will save money anyway. On SEP, you won't save money, but time, as your instructor can create any useful situation, failures, and so on. You will also be much more relaxed in an FNPT-II than in the actual aircraft. I made that part by cannes-aviation, a good FTO located in Cannes (LFMD), on the french riviera. They have several DA40 and DA42 with G1000, and a frasca FNPT-II based on DA42.

If you think that the FNPT-II will not reproduce the G1000 realistically given its complexity, you're wrong. In fact the sim does not repdoduce the G1000 at all, it INCLUDES an actual G1000 ! Garmin designed an external connection allowing to feed the unit from external signals from a simulator. This is why this time is really beneficial.

More on G1000 IFR nav settings and DA40 specifics to follow..

Trust the FADEC... but monitor it

2007-05-02T13:33:00.000-07:00

Sorry Thielert boys, but as any system, your contains some flaws. I will not put apart my "Plastic Evangelist" cap, or deny all what I wrote before, but will just report here a problem I had.

This happend after taking of from a 3500ft AMSL mountain airport. During climb, we (I say we because I was on the right seat, a friend of mine in the left seat, so I had a perfect observer position) reduced power to 95%, because the day was quite hot.

Passing 5'000ft AMSL climbing, we got a "low volt" warning, that went off immediately. Probably one of these problems that would not have been noticed on a classical not FADEC monitored engine.

Approximately 30 seconds later, the FADEC decided that 95% power was not a good setting, and it reduced to 65%. My fellow pilot did lower the nose to maintain speed, and we started troubleshooting the problem. However after 15 seconds, not even the time to switch to FADEC B to see if its perception was better, the engine was again running under 95%. To say everything, I must add that the air was quite turbulent, so the hypothesis of an unwanted throttle movement was not irrealistic.

We reported that to the maintenance, so the data has been inspected by a Thielert approved mechanic. This is where the FADEC played its black -box role perfectly. The mechanic could confirm:

1) the low volt transient alarm
2) the power loss
3) the fact that the throttle was not moved !

The problem had been reported to Thielert, and it was unknown at this time. I will report on this if I get an update.

This event was of no consequence as it did not happend in a critical phase of flight. However, should it happend immediately after take-off on a short runway, with 4 on board, this could be more critical.

To be a bit more analytical, this kind of problem can happen on any plane, with any type of engine. What makes it feel slightly different with a FADEC engine is that it alerts you about all trouble, but you're left with so few things to do (switch to FADEC B), that you can feel power-less.

Something more about switching to FADEC B. If the FADEC A fails, it will switch automatically to FADEC B. This is the only case when it will happen. If this automatic switch does not take place, a switch allow to force FADEC B.

Most of the alerts however do come from sensor problems, and if FADECs are doubled, most of the sensors are unique, feeding both FADECs.

If you think now that these bloddy plastic engines are risky and full of single points of failure, please re-open the AFM of your airplane / engine. You could be surprised by the number of single points of failure...

Follow me to next: G1000 transition tips

Plastic engine performance

2007-05-01T11:43:00.000-07:00

I must say something here before starting discussing plastic performance. I did not had the opportunity to fly the same aircraft with classical and plastic engine, so I can not compare pure engine performance. It is obvious that performance does not depend of engine only, but I will give here some engine performance figures.

As mentionned earlier, the FADEC gives some engine indications that are quite unusual compared to classical engine.

The classical injected engine with variable pitch prop is managed unsing Manifold Pressure (MP), Prop RPM, and Fuel Flow (FF). A diesel engine is managed using Load (in %). The instruments also indicate RPM and FF, but the pilot has no direct impact on those parameters. RMP and FF are indicative only to help monitoring.

RPM is clearly not a performance indicator, but FF is interesting. The example I will base my comment on is using a DA40D (classical instruments), with three mid-weight persons on board, on a quite normal summer day. Departure from Sion (LSGS), 1500ft AMSL, 20 °C.

Until 7000ft AMSL, flying at about 85 kts, VSI remains above 700fpm. Regarding engine parameters, the power is maintained to 100%, and remains so until 7000ft AMSL, then it slowly decreases. FF is slightly above 6 USG / H until to about 5.8 when reaching 13'000ft.

The climb stopped there to circle the local mountain peak. En route we set power to 70-75%, and FF remains arround 5 to 5.5 USG/H.

This is not a performance issue, but remind that during the whole climb, the power lever was left untouched. No RPM to set, no MP to re-increase in climb, and no mixture to set.

In terms of flight planning, the value of 6 USG/H is a safe standard. Anyway, most of plastic engine planes have huge tanks.

To close this pose, here is a picture of the standard AED / CED displays coming with Thielert engines.

More on these displays in a next post

G1000 vs. GNS430 / 530

2007-04-30T10:37:00.000-07:00

When I started my G1000 training, which comprised both theory and practice, the first question was "Are you current with the GNS430 ?". Yes was definetly the answer. I had extensive training and knowledge of the 430, on which my instructor insited a lot.

The G1000 trainer then said that I would have trouble with the G1000. What a surprise, and a douche froide (cold shower). Later on, I understood it was true.

What I will write here after concerns only the flight planning part of the G1000 / GNS430, in terms of instruments they obviously have nothng in common.

The good Garmin philosophy is respected by the G1000, so you find the FPL, Direct, CLR, ENT, PROC buttons, and the MENU key. What is new is the series of "soft keys". This is a series of keys below the screen, with no marking on them. Their function differs according to the currently used menu, and this function is indicated on the screen.

This is the big change you will have to deal with as a 430 user. Typically, when you finished to fill your flight plan in a 430, what will you do ?

Menu -> Activate ? Correct. But if you do so on a G1000, you won't find an "activate" entry in the menu. So, what ? Look at the soft keys below the screen, and one of them is labelled "Activate". That's the big idea of softkeys: offer the most frequently used functions directly.

The same applies to the procedures. To select a departure, press the PROC button, then the softkeys will become "select dep", "select arr", and "select app". So press "select dep", then the list appears, and one of the soft keys become "activate", so once you finished scrolling, press this softkey, and you're done. No more use of the menu key except for advanced / less frequently used functions.

Not only you can gain time with the softkeys, but moreover the corresponding items DO NOT appear in the menus anymore, and that's why my G1000 instructor was correct: in some aspects, being GNS430 proficient can be initially slowing you down when learning G1000.

More on G1000 NAV settings and engine performance in the next posts...

G1000 - Get rid of the six-pack

2007-04-28T08:58:00.000-07:00

Apart from plastic body (still no news about the gelcoat problem...) and plastic engine, the bigger change recently is certainly the plastic instruments - a.k.a glass cockpits.

This change has been made in steps, from years now, but the revolution is now complete.

One of the first step was probably electronic HSI like sandel tubes, which presented HSI on a small CRT tube, with additional route information. In parallel, GPS coupled with databases like the famous GNS 430 / 530 familly did bring moving maps in our cockpits.

An other step was the introduction of "low cost" inertial devices, allowing to replace the good old mechanical gyros, providing electronical attitude information.

Mix all of that together, and you obtain a G1000. I won't say a lot here on concurent product like Avidyne Entegra as I have no flying experience with them. However one must note one advantage of the G1000 over its competitors: it is the only one to integrate GPS and COM/NAV boxes. With Avidyne, it is still necessary to have separate GNSs.

So, when you fly a glass cockpit plane, the classical six instruments are all represented symbolically on the screen in front of you. And by represented, I don't mean "replicated as the mechanical". Typically, speed and and altitude indicators are in form of sliding tapes, not with round dials and needles.

My progression during the conversion to G1000 was in steps:

1) Get used to the HUGE attitude indicator that fills the whole screen
2) Find where information is
3) Sort out where the knobs are
4) Fly the bugs, not the figures

All of them will be detailled later, but here are a few words on each.

1) The vertical displacement corresponding to a given pitch change is much larger than on a classical horizon. This can be disturbing, when you're used to move your horizon by a few millimeters, to move it by centimeters to establish climb attitude.

2) Any IFR pilot is used to the T layout. This no longer exists with G1000, and even if the reading of the Primary Flight Display (PFD) is logical and easy, some training is needed.

3) In an electromechanical cockpit, each knob is situated in the corresponding instrument, i.e. baro setting on the altimeter, HDG bug and CRS selector on the HSI. As information is on the screen of the G1000, the knobs are all grouped on the side. Finding the proper knob can not be based on the instrument location, and there is noting worse than turning the baro setting instead of the CRS selector (based on my own experience...)

4) Even when flying with classical instrument, what we look at is the position of the needle, in the geometrical sense, not the actual values. Typically, when maintaining an altitude in cruise, one just manage to keep the needle vertical. This seems obvious, or even silly, but when flying with a G1000, there is no such thing, but a vertical tape with a bug you can set. The equivalent of keeping the needle vertical is to keep the bug aligned. Trying to interpret the figures displayed beside the tape is just not possible, and will lead to serious delay in the scanning.

As mentionned eariler, I will develop all of these topics, but the first conclusion is that conversion to G1000, even for VFR only, requires both theoretical and practical training. This is not an easy transition.

SyS