Do Fuel Injected aircraft really need mixture controls?

[Snow]

I would have though fuel computers would be able to automaticly ajust for air density and the mixture knob has remained due to some FAA regulation. Anyone know?

[Cheechako]

. . .and for that matter, why not electronic ignition. Dump those old-school magnetos for something a little more sophisticated.

I think it's hard to get the FAA to sign off on those things for the GA world and the price of testing and certification is too much for the manufacturers to swallow.

Just my highly uninformed opinion!

[El_Cid_Av8or]

Keep in mind that you're talking about a mechanical fuel injected engine, not a computer-controlled fuel injection engine. Common light GA aircraft don't have engine brains like a Honda Accord so the mixture lever is still needed and is usable. Take a look at a new C-172SP. Lean the mixture and the EGTs will rise (don't do this in a climb, only straight and level or in a descent).

As far as computer-controlled ignition in light GA aircraft, I'm sure it's in the ver near future. Any one that I would fly would have at least two backups to the primary one though.

Anyone care to shed some light on how the Cirrus SR-20 and SR-22 controls the RPM and manifold pressure with just one lever and get it right all the time?

Also, to add fuel to the fires of testing and certification, think about liability insurance. Example: Why does a replacement muffler for a Honda Accord cost less than $200 (stock replacement) but one for a Piper Arrow costs over $900? Answer: Insurance jacks the price up.

[EatSleepFly]

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Common light GA aircraft don't have engine brains like a Honda Accord

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Thank god. Who would want to fly in something powered by a Honda?


Just kidding all you Honda drivers!

[Snow]

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Who would want to fly in something powered by a Honda?

[/ QUOTE ]

*Laughs* I'm not a particualar fan of Hondas, but I'd say they make better engines than most, really that's what Honda does, they makes engines, for boats, cars, motorcycles, lawn mowers, chain saws etc etc
Isn't continental and lycoming still using push rod engines? geez

[sbav8r]

Honda is trying to certify an aviaiton engine, I'll try to find the link. http://world.honda.com/news/2003/c030304.html

[pilot602]

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$900? Answer: Insurance jacks the price up

[/ QUOTE ]

Certification plays the biggest role in the high price. Also, add in that (talking whole aircraft here) are all still built largely by hand and these guys are trying to seel these things to a market of roughly 1% (when you add in busineeses) of the total U.S. population and the way to make money is by higher prices. Things like cars can be priced at slighlty above cost because they make their money through volume.

[ready2fly]

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Honda is trying to certify an aviaiton engine..

[/ QUOTE ]
Grrreeeeaaaat. Then all the young punks will be flying them with those fart mufflers and funky paint jobs.

[pilot602]

And a big a$$ rear spoiler that serves absolutely no aerodynamic purpose ...

[sbav8r]

That's right G! I gots my viser on upsides-down, seat laaaaiiiiid back, arm over the yoke wit dat thumpin bass comin outa da back from the two 12s, and when I crank dat cessna over it sounds like a pissed off mesquito.

[Eagle]

Re: Do Fuel Injected aircraft really need mixture controls?

yep.

the testing and PMA/issues with getting anything approved for aviation is what makes it expensive. a few years back the president signed into law the product liability act, which basically cleared manufactures of liability after a number of years. I don't recall exactly but it was after 10-15 years I think. (someone go search on AOPA's site. )
it was a start, but did little in the real world.

You can go to Best Buy and get a car CD player for 100$, but you need to spend 1000 to buy the same quality one and put it in your airplane... give me a break...

[ananoman]

The DC-3 actually had automatic mixture contol. For ground ops and takeoff and climb it would be left in 'auto-rich', cruise was in 'auto-lean'. The only time the manual mixture control was used was during engine start and during emergency single-engine ops. The carburator had an aneroid capsule that would expand and contract just like the one in an altimeter to adjust the mixture. It was complex and needed precise adjustment, but they work quite well.

Electronic control is coming in the form of FADEC or Full Authority Digital Engine (or Electronic) Controls. The new systems will monitor each cylinders EGT and CHT to automatically adjust the mixture for each cylinder. They will also adjust spark timing for best power at take off or economy in cruise. Add on electronic ignition systems with variable spark timing can be retrofitted to many current engines and the fuel cost will repay the cost of the system if the aircraft is flown enough.

[aloft]

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Anyone care to shed some light on how the Cirrus SR-20 and SR-22 controls the RPM and manifold pressure with just one lever and get it right all the time?

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"Right" is a highly subjective term. "Adequate" is probably closer to the mark.

The Cirrus prop control has basically two positions; at a certain throttle lever setting, the prop control arm drops into the lower position and starts bringing the prop control back as the pilot further reduces power. At Cirrus' traveling road show, the have a throttle lever assembly that you can look at to see what it's doing. Personally, I find it quite a low-tech, rinky-dink solution, one that makes it impossible to test the governor during before takeoff checks.

But damn if that Avidyne display isn't da bizzomb!

[pavelump]

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Grrreeeeaaaat. Then all the young punks will be flying them with those fart mufflers and funky paint jobs.


[/ QUOTE ]

Yeah, but just think of how much more business there would be for the FL CFIs!


Dave

[El_Cid_Av8or]

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As far as computer-controlled ignition in light GA aircraft, I'm sure it's in the ver near future.

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I think the future is already here... Take a look at FADEC - Full Authority Digital Engine Control. Lancair is trying to take advantage of it for the Columbia 400. Here is a LINK.

[smokey1]

sbav8r ,
I find you r previous post to be very inapropriate. I know what you're getting at and I don't think there is a place for it in these forums. Let's use them for what they are for, the love of aviation, and not the slander of any particular ethnical group.
Smokey............................................ ...

[aloft]

Don't get your panties in a bunch, Smokey. I think what SB's getting at are stereotypical "rice rocket" drivers, who tend to pretend they're "straight outta Compton" regardless of their actual race, creed or color. Most kids I see acting that way are Asian or white.

In other words, it's not a racial slam so "don't be hatin'!"

[sbav8r]

Smokey
I'm not making fun of any ethnical group. I am however making fun of the "Rice Rocket" group that turn Honda's and Toyota's into ridiculous looking wannabe sports cars.

Sorry you took it the wrong way, I can assure you I meant absolutely no dissrespect to anyone other than the previous mentioned group.

If you happen to belong to that group then you have every right to be offended by my post. Otherwise, you might be getting the wrong idea or looking way too into it. Ethnicity was never in my mind at the time I wrote the post.

[Acadia]

I know this text was linked to a while ago, but this seems like an appropriate time to bring it back. The old link went right to an ebay auction. I saved the text for future enjoyment.


"You are bidding on a 600 Watt AMP + 2, twelve inch MTX subwoofers in an enclosed box. This system is pretty sweet, its got loud distinct bass, nothing to obscene, if you have an SUV or a truck this is perfect, it comes prewired already, just enough to feel your music, but not to irritate anyone else, or you can if you tweak it, or if your a loser who drives a Civic with a type R sticker, racing stripes, blasting really bad rap music through your suburban area with your pretentious "I’m 21 but I’m still in high school girlfriend" while driving with your hand up on the top of the steering wheel exposing your underdeveloped pasty white vitamin deficient arm and wearing your backwards BS upside down visor hat while feeling the tacky as a "Florida vacation" single diamond earring in your ear, If you are this person...with any luck the sun in its precise celestial positioning as you putter on by...will reflect its scorching rays into your earring, bouncing intensely in your rearview, and finally making contact with your eyes through the thin cheap lense of $5 gas station Oakley rip off glasses.. then burning your retnal cones into smoldering melting gobs of ocular material as you are blinded by the purest form of energy in our known universe, and as you scream no one can help or hear you because they don’t know what’s going on since the weed whacker sound of your ###### tiny little muffler which makes the Civic sound like a 747 rages on underneath making everyone turn at disgust and comment to thier husbands or wives how much of a dickweed you are by attaching that automotive abnormality to your stock economical daily driver engineered by Japanese Automotive specialists to fit the needs for entry level business workers in their early 30's, however your pathetic looking $11,000 car which you want to look like a friggin spaceship with redundant ground effects is now out of control since you are blinded, and as your car plunges off the side of a cliff while you scream in the purest form of terror while knowing you have lived a horrid excuse for a life, by doing the bare minimum in every facet of existence, while getting fired from one pathetic job to another, the majority of your time spent slacking smoking dope, getting kicked out of school, polishing your "game" on sweet innocent underage girls you eventually 'de flower' through exhaustive yet succesful attempts to get the date rapist drugs you have stashed in the glove compartment, into your poor victims drinks while offering them to take the "Pepsi Challenge" while making your mother hate you, and your poor father who wishes he had a daughter instead of your pathetic ass, since a girl would be more of a man than you ever were, like the occasion when you were hit in the arm by a wild pitch in little league, then you cried like a fat kid who dropped his ice cream cone, I'm already envisioning you impacting the rocks below, in a spectacular fireball ignited from the residue hairspray from your girlfriend plastered in the fabric passenger seat, blinded by your earring, deafened by the loud "Bling Blingin", and I will smile and roll around on the ground in orgasmic delight while you are consumed by flames whose intense heat and fury will liquefy your bone marrow that I will use to make jelly beans out of and eat them happily at your funeral as midgets dressed like Alex 6005321 from "A Clockwork Orange" dance around your coffin to loud industrial style techno music and strobe lights, and I will sleep soundly at night knowing another successful conquest of Darwinism has been attained. So...you can either use the system I'm selling like the fore- mentioned guy did, or you can buy it from this Cadet and use it properly and enjoy the compliments people will give you as you pass and let them listen to your outstanding taste in fine diverse music. Disclaimer: -No..Im not crazy...Following my 8 years of Military Service as a Naval Aviator, I plan to be a screenwriter. And no, you cant hire me...yet. I almost forgot, the RESERVE is UBER low, like dirt cheap. Shipping might be a bit expensive so if anyone is close to THE CITADEL, in Charleston South Carolina I can arrange a delivery, or you may pick it up. Thank you, if you have any questions please don’t hesitate to ask. My profile and feedback is immaculate. Thank you. EMAIL...KIRSCHE@CITADEL.EDU if you need to get in contact with me for any reason."

[smokey1]

Damn, I must have really taken that the wrong way, after reading my posts. I know everyone is in here for a common goal. Sorry for the harsh post.1 .
Smoke