The K8J project

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Arfang

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Sad news for the K8J:

My test flight alerted the EASA, which consequently contacted the french aviation authorithy about it. They have decided to revoke the K8J permit to fly. The reason stated is that a jet engine is not allowed on an ultralight.

However, the french regulations don't mention the type of engine, only the number and power are limited. That's what I'm going to explain to them.
They didn't give any other reason to terminate my permit to fly, they simply stated that this type is not allowed.

I don't know how it will turn out or even if I have a chance to fly again. But I know that I became a jet pilot for a couple of minutes and put the EASA on alert, and that's a win in my book. Apparently, the K8J was made out of Rearden Metal.

I want to thank the HBA community on more time for helping me achieve my goal.
 

jedi

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Good accomplishment. Do not give up easily. It really is not a jet engine, it just has a ducted fan fixed pitch propeller followed by an anti ice system and a windmill to conserve energy and keep the green community happy.

If that does not work send it across the border to a more friendly country. I would point out that France is the father of aviation and your project is intended to advance the (French or Swiss?) national image and is/was successful in that respect. Does the EASA require that you defect?
 
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Vigilant1

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Sad news for the K8J:

My test flight alerted the EASA, which consequently contacted the french aviation authorithy about it. They have decided to revoke the K8J permit to fly. The reason stated is that a jet engine is not allowed on an ultralight.
Very sorry to hear about this setback, and I hope you can work out a clear path to fly again legally.

Unsolicited and probably un-needed input:
Having dealt with large bureaucracies myself, the only words of advice I have is to try to make your intended result the >easiest< thing for those with the power to do. I've gone so far as to write the actual letters (with all needed justification attached) with their signature block already at the bottom, they just needed to print it on their letterhead and be done. I've found that if I make an enemy along the way or in any way question their expertise or authority, things get much harder than they need to be. I keep it as friendly and non-personal as possible, but (tactfully) make sure they know that I won't go away quietly, that I will be a constant presence in their lives until the system accommodates my request.
 

Arfang

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Thank you all.

Unsolicited and probably un-needed input:
Any advice is welcome!

For what it's worth, four Colomban Cri Cri homebuilts have flown with jets in France, but I guess your issue is more that you've converted a certified glider.

https://minijets.org/en/0-100/jet-cobra/mc15j/
Good point, maybe that's what the EASA thought. But the airframe was written-off and it is no longer a certified airplane. These jet Cri-Cris are registered as E-AB, mine is registered as an UL, different rules for each category. Since you linked the minijet website, I shall too:

http://minijets.org/fr/0-100/kingtech-k310g/as-k8j/

If that does not work send it across the border to a more friendly country.
French UL regulations are already very ''friendly'', a better place to fly would be hard to find.

The answer came back this morning and the stated reason is that even if the power of the airframe-engine system can be determined (P=F.v), it is the power of the engine alone that counts. I asked if I could at least keep flying the airplane until the temporary permit to fly expires in september 2019. If that's not possible then I'll probably convert the K8J into a K8TP.
 

jedi

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Thank you all.

...........

The answer came back this morning and the stated reason is that even if the power of the airframe-engine system can be determined (P=F.v), it is the power of the engine alone that counts. I asked if I could at least keep flying the airplane until the temporary permit to fly expires in september 2019. If that's not possible then I'll probably convert the K8J into a K8TP.
The engine as installed on the airframe does not produce any power since it does not move. Power equals force times distance as a function of time. The distance the engine moves relative to the airframe is zero. Therefore the power of the engine alone (not associated with a moving airframe) is zero. It is "the power of the engine alone that counts".

Jet engines produce thrust not power. If the engine does not produce shaft power the power output is zero until you put it on a moving airframe. It appears the authorities chose not to recognize that the airframe is moving.
 

ypsilon

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Mar 1, 2016
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273
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Austria
Sad news for the K8J:

My test flight alerted the EASA, which consequently contacted the french aviation authorithy about it. They have decided to revoke the K8J permit to fly. The reason stated is that a jet engine is not allowed on an ultralight.

However, the french regulations don't mention the type of engine, only the number and power are limited. That's what I'm going to explain to them.
They didn't give any other reason to terminate my permit to fly, they simply stated that this type is not allowed.
This sounds a lot like changing the rules during the game. If they write up the rules they should make sure that one is on the save side when abiding to them. I've had similar situations here in Austria, and in Germany as well, when they made up rules that had enough room for interpretation that different authorities arrived at different conclusions.

What exactly is the problem with the jet-engine? I didn't find anything conclusive in the EASA regulations. In the relevant regulation Annex II of 216/2008 (EASA Basic regulation) it says (amongst many other not relevant things that:
Aeroplanes, helicopters and powered parachutes that do not have more than two seats, a maximum take-off mass of no more than as follows, and, for aeroplanes, having the stall or steady flight speed in land configuration not exceeding 35 knots calibrated airspeed:

300 kg for a single-seater land plane/helicopter
450 kg for a two-seater land plane/helicopter
330 kg for a single-seater amphibian or floatplane/helicopter
495 kg for a two-seater amphibian or floatplane/helicopter, that also falls below both maximum take-off masses, when operating as a float or land plane/helicopter.
472.5 kg for a two-seater land plane with an airframe mounted total recovery parachute system
315 kg for a single-seater land plane with an airframe mounted total recovery parachute system
Single and two-seater gyroplanes with a maximum take-off mass of no more than 560 kg

fall under national regulation.

I am not a lawyer, but I haven't found any definition of "land plane" in the EASA regulations, that would rule out jet engines.
 

Arfang

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The engine as installed on the airframe does not produce any power since it does not move. Power equals force times distance as a function of time. The distance the engine moves relative to the airframe is zero. Therefore the power of the engine alone (not associated with a moving airframe) is zero. It is "the power of the engine alone that counts".

Jet engines produce thrust not power. If the engine does not produce shaft power the power output is zero until you put it on a moving airframe. It appears the authorities chose not to recognize that the airframe is moving.
You're absolutely right.

We could also measure the power output by torque times angular speed of the shaft, but it makes no practical sense. On a lighter note, I could register my airplane as a glider, since the power output of 'the engine alone' is zero.

This sounds a lot like changing the rules during the game. If they write up the rules they should make sure that one is on the save side when abiding to them. I've had similar situations here in Austria, and in Germany as well, when they made up rules that had enough room for interpretation that different authorities arrived at different conclusions.

What exactly is the problem with the jet-engine? I didn't find anything conclusive in the EASA regulations. In the relevant regulation Annex II of 216/2008 (EASA Basic regulation) it says (amongst many other not relevant things that:
There is no issues with the EASA, they simply wanted to make sure that the airframe is not certified and does not have manufacturer identification marks/serial number anymore. It's purely a french issue involving the DSAC.

I totally agree that it's like changing the rules during the game. I even pointed to them that they issued a permit to fly for the K8J. And that I invested time and money in that project after receiving their approval.

The DSAC didn't answered. The simply told me to see if I can register it as a self-launching glider if a category allowing jets will be created in a distant future. As I mentionned earlier, if a solution involving a jet isn't found I'll switch to a turboprop.
 

ypsilon

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You're absolutely right.
I even pointed to them that they issued a permit to fly for the K8J. And that I invested time and money in that project after receiving their approval.
I think this a classical case of "official liability". IOW they should cover your expenses then, at least.
 

Chris Young

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Feb 19, 2013
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Make sure first with DGAC that you wouldn't have the same problem with the turboprop.

As far as I know they only consider piston engines and turbine engines, so turboprops and jets fall in the same (latter) category.
 

cluttonfred

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I know it's not as cool as a jet, but any one of several small, light, two-stroke, paramotor engines ought to be able to put out more thrust than your 32 kgf/70 lb turbine, probably improving take-off and climb at the expense of top speed and power-off glide. If you want to stay in the microlight category, then the Vittorazi Atom 80, Cors-air Black Bee, Simonini Colibri, Radne Raket 120, etc. should all be viable options.
 

Arfang

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Make sure first with DGAC that you wouldn't have the same problem with the turboprop.

As far as I know they only consider piston engines and turbine engines, so turboprops and jets fall in the same (latter) category.
I sent them an email regarding the turboprop option. The answer just came back, I'm not restricted from installing a turboprop instead. I'll double check with them just in case.

They also answered why a jet isn't allowed: 'It was not in the mind of the lawmaker when he created these regulations'. First, it was the engine type, then the power output and now this.

I know it's not as cool as a jet, but any one of several small, light, two-stroke, paramotor engines ought to be able to put out more thrust than your 32 kgf/70 lb turbine, probably improving take-off and climb at the expense of top speed and power-off glide. If you want to stay in the microlight category, then the Vittorazi Atom 80, Cors-air Black Bee, Simonini Colibri, Radne Raket 120, etc. should all be viable options.
Thanks for the suggestion, I'll have a look at these engines if neither the jet or turboprop are viable options. But, as you said, jets are cool, what am I going to brag about if I can't say that I have my own private jet?
 

jedi

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I sent them an email regarding the turboprop option. The answer just came back, I'm not restricted from installing a turboprop instead. I'll double check with them just in case.

They also answered why a jet isn't allowed: 'It was not in the mind of the lawmaker when he created these regulations'. First, it was the engine type, then the power output and now this.



Thanks for the suggestion, I'll have a look at these engines if neither the jet or turboprop are viable options. But, as you said, jets are cool, what am I going to brag about if I can't say that I have my own private jet?
A simple wind mill and prop in the intake or exhaust should do the trick. May need a stater to straighten the flow if the windmill is too aggressive.

Kind of like the extra automobile tires added to the cement trucks to make them legal. You may not have those in France.
 

ypsilon

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Arfang,

I would not let them get away with it so easily. You built a pretty machine, spent time, effort, and money on it, and even told the "authorities" specifically what you were planning to do. The France, I know abides by the rule of law, which means that the law is what it says. Not what somebody thinks somebody else had in mind (or in your case: didn't have in mind) when the law was written. That's simply not how it should work. Evrything else leads to a bureaucratic dictatorship on the long run. Seriously.
 

cluttonfred

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I agree that you ought to appeal the decision to the DGAC, calmly and polotoely laying out in a letter the steps that got you to this point and reviewing why you believe that your project does meet microlight (ULM) requirements. As I remember, there is nothing in the French regulations that precludes a jet engine, it just specifies max power in kW. If you can find a manufacturer or government source giving the equivalent power of jet engines in general, or better yet your specific engine, in kW, include that and make the case. As long as your plane meets the weight and minimum speed requirements, it’s worth a shot.
 

Arfang

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Switzerland
Arfang,

I would not let them get away with it so easily. You built a pretty machine, spent time, effort, and money on it, and even told the "authorities" specifically what you were planning to do. The France, I know abides by the rule of law, which means that the law is what it says. Not what somebody thinks somebody else had in mind (or in your case: didn't have in mind) when the law was written. That's simply not how it should work. Evrything else leads to a bureaucratic dictatorship on the long run. Seriously.
I agree that you ought to appeal the decision to the DGAC, calmly and polotoely laying out in a letter the steps that got you to this point and reviewing why you believe that your project does meet microlight (ULM) requirements. As I remember, there is nothing in the French regulations that precludes a jet engine, it just specifies max power in kW. If you can find a manufacturer or government source giving the equivalent power of jet engines in general, or better yet your specific engine, in kW, include that and make the case. As long as your plane meets the weight and minimum speed requirements, it’s worth a shot.
I did that, and everytime I tried to prove that the engine meets UL regulations they changed the subject. This could go on forever, I'll give it another try (see below) and after that I'll swap the engine.

Also, there are some potentially good news: When I contacted the french UL federation to inform them of my first flight, they answered that there is already a jet-UL in France. I was able to get the name of the owner. I'll keep you informed.

I think in the U.S. A jet glider requires some pilot training/endorsement.
Even for a Part 103 jet glider?
 

BBerson

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A Part 103 jet ultralight pilot does not need any endorsement. But a K8 does not qualify under Part 103 because of weight.
 
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