844X Ups and Downs

June 14, 2016

OK plenty of stuff has gone wrong with my Evolution (N844X… Google it for pics), but the only way any of this can be WORTH IT is if we LEARN from our mistakes and build better systems and better operating procedures (checklists!) so as we move into the FUTURE,  these problems don’t happen again… to me or anyone else!

Put another way, the only way to BENEFIT from our mistakes is to USE them to EVOLVE.

Hmm… now that I think of it, Lancair DID call the airplane the “Evolution”, right from the start, so maybe they were hinting at this all along!

So here we go:

STARTING POINT:

The Lancair Evolution with the PT-6-42 engine is what happens when you attach an 850 hp PT-6A turbine to a carbon-fiber ballon. Climb rates of over 5,000 fpm, cruise speeds above 300 knots, all in a platform that can cover over 1,000 nm with reserves and can still fly at 60 knots for very low-speed take-offs and landings. Talk about a wide performance envelope!

With the Evolution, you get very easy access to all the little airports in the country, and connect them up to 1000 miles apart, with pressurization, air conditioning, and pretty good flight characteristics. More performance than a TBM but at a MUCH lower fuel burn and a FRACTION of the price! With the super light-weight carbon fiber body of the Evolution, that airplane just JUMPS into the air: The airplane hardly weighs anything at all! I can actually tell if my Evolution is fueled or not just by LOOKING at it! Since the airplane is just a carbon-fiber balloon attached to a light-weight PT-6, the FUEL on board weighs almost as much as the AIRPLANE! As a result, when empty, the Evolution sits tall on it’s main gear, nose pointed down at the ground. It looks like a cat that is about to pounce on something, back haunches raising the body up. When fueled, the weight on the main gear goes up so much from the weight of the fuel that the main gear sits much much lower. Now it looks like a low-rider car, aft gear compressed, nose pointing upwards! So I can request a fueling on a cross-country, go to lunch, and then tell at-a-glance from 50 yards away whether the plane has been fueled yet! Har!

The handling is fun like a helicopter, in that you have to constantly fly ALL AXIS in response to ANY CHANGE in POWER.

How could that be surprising when you have so much of it, in a plane that hardly weighs anything?

Touch the throttle?

OK.

The slipstream change demands countering rudder or the plane will yaw back and forth like a windsock in shifting winds.

The torque change demands countering aileron or the plane will roll like tippy canoe.

The speed change demands countering elevator or the plane will phugoid up or down, like, ummm… a race-car zooming up a hill? Sorry I’m running out of analogies here.

So the plane is always demanding full attention on all axis, like a helicopter.

Perhaps imperfect, but that’s what makes it FUN!

Oh yah and when you are flying it it is like having coffee being injected directly into your veins. I mean, the moment you hit that starter and get that turbine spool-up right in front of you, it is ON. The moment the fuel comes in during start you see 900 degrees CELSIUS (about 1,600 degrees F!) up front, the turbine spools up right in front of your feet to a scream, and the prop ramps up into thumping action, and you have to keep putting the thing into REVERSE DURING TAXI just to keep it from running away from you AT IDLE! Apply power for take-off and you can tell that you are basically strapped to a turbine as your are pushed back in the seat from the acceleration as the turbine connects (though an AIR-coupling only!) to that huge prop. Every moment of the flight you are kept in a hyper-alert state from the turbine screaming seemingly attached your feet, and control input being required on all 3 axis any time anything changes.

So it is a constant thrill to fly, but oh man there are plenty of problems too! (The trick is to LEARN from them so you can make the airplane ever-better.)

Let’s look through the main ones that I have had, and the solutions we are implementing to solve them… not just for now, but for all of my operations in the future as well! (…and hopefully OTHER people’s operations as well, if they read this post!)

I’ll list each major problem, and the solution we have come up with, which includes mods to the airplane, and EQUALLY IMPORTANTLY, MODS TO MY CHECKLIST! The CHECKLIST is literally as important as the airplane, because as I have learned, if you don’t have and follow a checklist that LISTS THE NEEDED PRACTICES, then your equipment that depends on that checklist might as well not even exist! I have been humbled by making mistakes in this airplane, and now vow to follow the checklist and operate this airplane as professionally as possible in the future!

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EVENT:

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Just the other day I was at 27,000 feet, 275 knots, in solid IFR in a front, when suddenly the engine began… ‘popping’.

It was sort of a THOOMP, THOOMP, THOOMP, with the ITT and torque dropping a bit with each drop-out of power. Power was dropping.

You read about (and, if me, simulate) this type of thing all the time, but when it really is happening, it is a bit terrifying.

About the same time, the smell of jet exhaust started to become rather strong in the cockpit. Not enough to SEE, but I could really SMELL jet-exhaust in the cockpit.

I declared the emergency and started down.

The temperature in the cockpit was coming up during the descent as always, so I engaged the cabin intercooler to send cooler air into the cockpit.

WHOOOOSH! Out went the air from the cockpit and the plane de-pressurized instantly… I was now above 20,000 ft with no pressurization! I grabbed for my emergency backup oxygen mask always under my right hand and was never so happy to get down to 12,500 ft in my life.

The engine was now behaving normally again, and I landed.

NOTE: Google Xavion. I had Xavion running on my iPad for the entire event, so had at least a dozen or so airports ready for a power-off glide for the entire event if I needed them. Thanks to Xavion, my only fear was the pressurization loss and exhaust in the cockpit.. the partial engine failure was of less concern! This let me focus on dealing with my emergency oxygen system and talking to ATC, since I knew that Xavion was presenting me plenty of gliding options to nearby airports, continuously, throughout the entire event. When ATC advised me of the NEAREST airport, I was able to tell him, straight up, in the middle of the emergency, that I did not need the NEAREST airport… I needed the BEST airport, runway length and width considered! And, since I had Xavion, there was no problem at all seeing what airport that was! (Phoenix Goodyear in this case)

So Xavion worked perfectly.. it was awesome. But what caused the engine surge, exhaust smell in the cockpit, and de-pressurization?

A simple little hose had come loose.

A little hose from the engine compressor to the intercooler that cools the pressurized air for the cabin.

When that simple little hose came loose, the compressor of the engine, which is used to supplying small quantities of compressed air to the cabin, suddenly had ZERO back pressure on the pressurization system (the hose had come loose!) and was just dumping compressed air right back into the cowling. This caused the compressor surge, which kicked the engine exhaust back into the pressurization system… and into the cockpit. Thus the burned jet-fuel smell in the cockpit! Finally, when I engaged the intercooler: All the pressurized air in the cockpit went right out of the plane though the now-dis-connected hose.

So one hose failure caused all those symptoms at once.

PROBLEM:

Pressurization failure and jet exhaust in cockpit.

SOLUTION:

Better, stronger, tighter attachment fittings to hold the little hose in place!

This could include flanges on the pipes that the hose hooks to, so the hoses cannot slide off the pipes!

Checklist for maintenance to really be sure that those attachments really are tight and secure, even under pressurization loads.

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EVENT:

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The hydraulic fluid that raises and lowers the landing gear might be hot near the engine, and cold in the back of the airplane, in flight.

OK.

So you land the airplane.

You go home or to the hotel or whatever.

Overnight, as the temperature of the hydraulic fluid all equalizes, the previously-hot hydraulic fluid contracts.

Overnight, as the temperature of the hydraulic fluid all equalizes, the previously-cold hydraulic fluid expands.

So, sitting in a hangar, a pressure builds up in the hydraulic system!

What happens next?

Well, the pressure build-up will either hold the gear down even MORE firmly, or retract it on the ground!

Now considering how luck works with bad design: Which one do YOU think we’ll get?

The gear retracts on the ground, basically all by itself, as soon as anyone tries to tow the airplane.

This has happened to 4 or 5 or so Evos, including once to mine.

Bang.

$40,000 in repairs and 4 months in the shop, replacing the prop, inspecting the engine, repairing the underside of the plane, etc.

At times like that, a Cessna 172 starts to look REEEEAAAAALLLLL good.

Because a Cessna 172 would still be delivering 100 knots at that point, while the Evo is delivering 0 knots and abut a $40,000 maintenance bill to go nowhere at all!

Argh!

I think the airplane should have been designed with an overflow valve to absorb the hydraulic pressure that builds in these cases, or an electrically-actuated solenoid that dumps that pressure when the airplane is shut down, or something like that. When I asked Lancair about this, first they told me to stop considering any design mods, then they told me that fixing this was not a priority for them, and then on my third attempt they ignored my email altogether. So OK, this is a problem they won’t fix. This is very, very, very scary because if you don’t dump all the hydraulic pressure using the emergency bypass as part of your shut down procedure, then the nosegear is likely to wind up collapsing whenever anyone tows the airplane the next morning! That really does cost you sleep, trust me.

Now, Lancair has provided a sort of partial work-around: Lancair will SELL you some locks you can attach on your gear after each flight that stops this from happening… for $265 per gear-leg. Three required. All for extra charge. Not included in the kit.

So, a million dollars for the airplane.

$265 per gear-leg extra to keep it from falling on it’s face when being towed at 5 knots.

Very frustrating!

PROBLEM:

Landing gear can collapse on the ground during towing.

SOLUTION:

Checklist item to engage emergency hydraulic bypass after landing to dump all pressure.

Checklist item to install gear down-locks after landing.

Checklist item to remove gear down-locks before flight.

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EVENT:

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The pressurization, HVAC, and electronic circuit breakers for the lights are all controlled by a touch-screen system called the MORITZ display.

What a wretched, wretched, wretched little piece of hardware. Normally I would feel bad about complaining about someone else’s work, but since Moritz routinely takes 6 months to do basic repairs and upgrades (including a 6-month wait that I had to go through to wait for a minor fix on mine), well, with that kind of customer support… screw ’em I’m telling all!

With an interface that seems to have been inspired by an Atari game system in the 1980’s, the display has an almost COMPLETE lack of diagnostic information, so that even if there ARE data-bus errors between the Moritz and the pressurization outflow valve that it commands, you could NEVER tell from looking at the display! Any ERRORS are literally NOT DISPLAYED! My pressurization system does not DE-pressurize the airplane properly for landing, but thanks to the lack of diagnostics, nobody can tell WHY!

As well, if you want to turn off the air conditioning, it is never clear if you are supposed to turn it off on the HVAC page (power) or the ECB page (ummm… power), because the interfaces look identical.. but if you choose the wrong one, the system over-rides you and turns the AC right back on again!

The buttons ALL LOOK IDENTICAL! Seat heat? Air conditioning fan? Strobe light? All identical in appearance. The programmers seem to have decided that the best way that they could show off their laziness was to make every button an identical, ugly, image, and just hap-hazardly jam a different label onto each button. The interface to this system is really just an embarrassment.

I hired a company called Vertical Power to build a replacement hardware for this system. They went about 200% over-budget, sold off the assets of their company, pocketed the cash from the sale to make their company empty and judgement-proof, and then gave up without finishing the job. Marc Ausman, the president of Vertical Power at the time, said that the Verge Fund, which funded Vertical Power, would sue me, and take me house and my car, if I did not sign a statement saying that the  job was done… even though it most certainly was not, to any safely useable level.

PROBLEM:

You cannot tell what is going on with your pressurization and various other systems, either for flight or other diagnostic purposes.

You cannot control the various electrical systems in a user-friendly manner.

SOLUTION:

Replacement for the Moritz that does not suck donkey-balls.

Such a replacement would have a modern interface, good diagnostics, and preferably also act as a backup for many of the airplanes displays… a copy of Xavion running in that box would back up airspeed, altitude, heading, synthetic vision, weather, end even give power-off guidance in the event of engine failure.

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EVENT:

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The Lancair Evolution normally ships with a PT-6A-135 engine, of 750 hp.

I chose the the Aerotek firewall-forward cowl and engine upgrade to the PT-6A-42 engine, of 850 hp.

The idea was that the Aerotek cowl is a little more streamlined than the standard cowl, and the extra 100 hp could give a bit more performance.

Better climb and cruise.

AND, the PT-6A-42 engine is a TINY BIT MORE EFFICIENT than the PT-6A-135 at very high power settings, thanks to it’s extra compressor section!

AND the bigger engine does not add any weight to the airplane, because it comes with a lighter-weight prop that offsets the slightly heavier engine.

So, more power and more efficiency and no weight gain. SOUNDS like a great idea…………….

BUUUT it doesn’t work out quite as well as we hope, and here is why:

The Garmin G0900 avionics package that the airplane uses does NOT have a profile for the -42 engine!

So the Garmin has to be set up for the -135 engine!

So, as soon as you try to USE the power of the -42… the Garmin THINKS that you have a -135, starts to panic, and squawks out text and audible alarms that you are over-torquing the engine! So if you try to USE the power that the -42 HS, then there is a steady stream of alerts beeping in the cockpit!

So you can’t really USE the power of the -42.

You might as well have a -135 under the hood!

(NOTE: Yes, for hi-altitude climb, the -42 can HOLD 750 hp up a higher altitude, allowing a SUSTAINED climb rate to a higher altitude, but this is a fairly minor improvement)

So, for climb, the -42 engine can’t really be fully utilized, because Garmin simply has not gone to the effort complete their G900 product to include support for that engine.

But what about cruise?

Well, here is the reality of the situation: At 28,000 feet, the AIRFRAME of the Evolution is most efficient at 170 knots true airspeed.

Go any slower? NOT EFFICIENT! Your induced drag increases, and it would actually take MORE fuel to go SLOWER.

Go any faster? NOT EFFICIENT! Your parasite drag starts coming up and you run into an aerodynamic brick wall.

In fact, if you try to USE the extra power of the -42 engine, you will only go a TINY BIT faster, but the fuel-burn rises HUGELY… to over 40 gallons per hour when pushing through 300 knots. Your gas mileage falls from 10 down to 8 miles per gallon: a 20% reduction. It just does not seem worth it to lose 20% of your efficiency for that small extra bit of speed.

So the ENGINE is only efficient if it is running FAST (turbines gotta SPIN!)

The AIRFRAME is only efficient if it is going SLOW (big wing for low stall speed wants to go SLOW!)

So there is NO WAY to operate the airplane in a really efficient manner!

If you go SLOW, you are out of the sweet-spot for your ENGINE!

If you go FAST, you are out of the sweet-spot for your WING!

You can’t win!

So you see you can’t have both a big turbine engine and a big wing at the same time and still be efficient.

The engine wants to go fast (to spin the compressor at design speed!)

The wing wants to go slow (to minimize parasite drag!)

You can’t keep them both happy at once.

This is the case for ANY airplane.

There is no solution to this with a turbine engine.

Playas gotta play, turbines gotta spin.

So turbines need to be on planes with tiny wings and high stall speeds so the airframe wants to race along like the engine does.

And that is just NOT the case with the Evo… that big wing wants to go just 170 knots at 28,000 feet, not 300 knots!

NOW, this is where RECIPROCATING engines come in!

Recip engines are perfectly happy to run at LOWER power settings WITHOUT losing efficiency!

They trap all their air in the cylinders no matter how fast or slow they run, so they can run slow just fine, unlike the turbines which cannot trap air in cylinders, so depend on 100% RPM to keep their whole process going.

So with a RECIP engine that could slow down to the speed the wing wants to go, a REALLY good airplane COULD exist here (good news on this at the end of this post!)

PROBLEM:

Big turbine ENGINE makes it in-efficient to fly SLOW.

Big WING makes it in-efficient to fly FAST.

SOLUTION:

A reciprocating engine would address one of these issues.

A smaller wing would address the other.

But both would reduce the astronomically-wide performance envelope of the airplane by giving it a lower top-speed or a high-stall-speed… you see how I am just describing a Lancair-IV here?

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EVENT:

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Every single time I go anywhere and ask the plane to be towed to the hangar and the linemen go to hook up the towbar, they look at the airplane like it just came from Mars.

Lancair, for reasons that I simply cannot fathom in any Conceivable Universe, made the towbar attachments DIFFERENT THAN ANY OTHER AIRPLANE ON THE PLANET, making it IMPOSSIBLE FOR ANY TOW-CART ON EARTH TO HOOK UP TO THE AIRPLANE.

THEY LITERALLY DELIVERED AN AIRPLANE THAT CANNOT BE TOWED BY ANY TOW-CART I HAVE EVER SEEN!

They made the little bars that you hook on to too small for any tow-cart on the planet to hook up to.

So, I had to have custom sleeves added to the towbar, AND NOW EVERY TOW-CART CAN TOW THE PLANE!

PROBLEM:

The towbar attach points are the right size for ZERO tow-carts on Earth.

SOLUTION:

I added some steel sleeves onto the end at a wider radius, so now the plane can be towed by ALL tow-carts on Earth.

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EVENT:

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There is only one electrical bus and it will fail at some point in the future.

PROBLEM:

There is only one electrical bus.

SOLUTION:

There should be two electrical buses.

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SUMMARY:

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OK, a lot of the stuff above is already addressed by design updates, and I know that more can be, so an ever-brighter future is pretty much assured. Heck, it’s evolution!

Now, I think I am going to go for a drive in my wifes’ Tesla Model S.

THAT machine is the ONLY machine in my life that does EVERYTHING PERFECTLY.

PS: As I write this, Lancair has just provided, after almost a DECADE of delays, a reciprocating-engine option for the Evo, using the new Lycoming IE2!

This engine option apparently gives an Evo 210 knots true airspeed at 17,500 ft on an astonishing 12 gallons per hour of fuel.

That is MORE than 2/3 the PERFORMANCE of the turbine Evo at LESS than 1/3 the fuel!

Well over TWICE the efficiency!

Well over TWICE the range!

And, this is at an altitude of just 17,500 instead of 28,000, so the airplane is much, much, much SAFER in the event of a cabin de-pressurization!

So, that Moritz display and pressurization system still seem to me to be one step above garbage, but at just 17,500 ft, with a backup oxygen mask… the safety should still be really really good… and the speed and range and efficiency are simply beyond phenomenal!

As well, at the lower speed, the wing-size works out to be a lot closer to ideal!

This is reflected in the stellar speed and range that the recip engine can deliver by just slowing down a little bit.

So the RECIP Evolution looks to be a far, far, far better solution than the turbine due to:

-the ability to run at lower power settings to fit the big wing without losing efficiency

-the lower power and SLIGHTLY lower speed but with MUCH greater efficiency inherent in the recip engine

-the lower cruise altitude, making the terrible pressurization system and interface a much less problematic issue

-the near-zero fuel flow at IDLE, allowing you to keep all your fuel for flight, unlike the turbine which wastes 23 gallons per hour at IDLE!

… so, especially with the new recip engine, Lancair is knocking down these problems in the Evo, one by one!

The recip engine Evo with the IE2 looks to be simply amazing. Lancair has published some absolutely stunningly-high cruise speeds and vanishingly-low fuel flow flows for the IE2 recip Evo… if those numbers really are true, and the plane can get them at 17,000 ft where a cabin de-press would not really be dangerous, then that will make an INCREDIBLE airplane. Just incredible.

Just don’t try to tow it without thinking really carefully about all the ways that could go wrong.