Small front flaps on MCI

[Hi yo silver]

I'm wondering about the purpose of the small rubber flaps located below the front bumper on some MCIs. Take a look at the beautiful bus on the cover of the March issue. I have seen them on some buses, but mine doesn't have them, and they didn't come to mind until I noticed them on that one. Hmmm...
Dennis

[JohnEd]

The less air you have roiling around under the bus the more "slippery" the bus will be going down the road.  Called an "Air Dam" in auto circles but there it is used to reduce "lift" but it also reduces drag as a parasitic plus.

It costs nothing to "operate" a air dam, but even at the very small return on investment you are making out.  Any conservation on fuel usage is a good thing to do for the planet and should provide motivation in itself.

Putting a dam in front of the engine bay will do the same thing on a smaller scale.  The reason for doing that is to lower the "ambient" air pressure in the engine bay.  This aids the rad fans in a MCI or any system that pushes air into the engine bay.  This reduces the water temp as more air flow means more heat transfer and that means a cooler engine.  How much good it does is always debatable but if you fan is turning easier then you are using less fuel to turn it going down the road.  Rad fans on a 8V92 consume 60 HP I am told and any help should be a HELP.  Forget about air flowing in the engine bay cooling the engine as that is a false payoff.  Give some thought to cutting a slice out of the dam in front of the rear wheels as the differential needs a flow of air to cool it.

A bidness called "Mill Supply" sells conveyor belts and will have scraps in the trash bin.  Mills wil also have them in the trash.  Look at what they are "conveying" for an idea of how tough the belt is in that scrap heap.  If it is transporting feathers you should probably pass.  Hard rock belt is good stuff.(LOL and  a big GUFFAW)

Some have put the dam under the rear bumper and that is a bad thing to do.  It also launches dust and sand up onto the toad.

Way more info than you wanted....right?

John

[Hi yo silver]

HA! I knew that!  ..Just kiddin'
Thanks John! I wonder why they didn't just put a long one all the way across? That's interesting. Leave it to MCI to figure it all out. I'm just feeling smug because I have one. ..And maybe a little jealous because it needs something to make it more streamlined. Ha! I'm gonna put some on mine, so next time some poor busless soul comments on fuel mileage, I can just tell 'em it's slicker than it looks. LOL
Dennis     

[robertglines1]

Ground effects? spoiler next?

[gmbusguy1]

If anyone actually thinks that a small piece of rubber under the front of a Bread box will help with aerodynamics I have some swamp lots for sale in Florida to sell them.

Really, the purpose of the flap is to keep road debris ans water (the elements) out of the Horn area

Chris

[artvonne]

If anyone actually thinks that a small piece of rubber under the front of a Bread box will help with aerodynamics I have some swamp lots for sale in Florida to sell them.

  You mean like those tiny little metal tabs on the trailing edge of a wings ailerons or rudder to correct trim? Or the difference between an air scoop and a NACA duct? Little things you wouldnt imagine could do much actually can do quite a bit. No, its not going to make a giant change, but it will make a difference, and a greater difference the lower it rides and the more air it pushes aside rather than letting it tumble underneath.

[JohnEd]

If anyone actually thinks that a small piece of rubber under the front of a Bread box will help with aerodynamics I have some swamp lots for sale in Florida to sell them.

Really, the purpose of the flap is to keep road debris ans water (the elements) out of the Horn area

Chris

Me, Me....I believe that.  I did say that it might be a miniscule difference.  Now 'bout that land you have for sale in Floridaville.  Lets hear bout that.

[JohnEd]

HA! I knew that!  ..Just kiddin'
Thanks John! I wonder why they didn't just put a long one all the way across? That's interesting. Leave it to MCI to figure it all out. I'm just feeling smug because I have one. ..And maybe a little jealous because it needs something to make it more streamlined. Ha! I'm gonna put some on mine, so next time some poor busless soul comments on fuel mileage, I can just tell 'em it's slicker than it looks. LOL
Dennis     

The mud flaps are required by law.  More Gummint interference crapola.  Now running it all the way across would just be a gesture of good intentions and a nod to the Greens.  Can't have that.

Those "anti Vortex winglets have been a known commodity for some time now but they had to become a fuel savings "feature" before they were made available.  What do you bet that Air Bus didn't start making their wings that was and force Boeing, kicking and fighting and screaming, to follow suit?  I noticed that De Havaland up in Canada has had under-turned wing tips since day one for low speed stal and lift things but a Cessna or piper didn't last time I checked.  I know, O know, I have even less quals in aeronautics than buses but does that prove the question doesn't have an interesting answer?

John

John

[buswarrior]

Run the coach through a deep pot hole style puddle and come back and tell us what those flaps under the bumper might be for.

All over the windshield.

happy coaching!
buswarrior

[artvonne]

  I know, O know, I have even less quals in aeronautics than buses but does that prove the question doesn't have an interesting answer?

John

  We can always count on you for an interesting answer, lol.

  The biggest reason there arent more winglets and other aero mods seen in general aviation has more to do with cost than anything. Some of those aftermarket wingtips can cost over $2000, and then you need all that FAA approval and 337's and all that. And the first time come nimrod clips a wing tip on aa hanger door, oh dangnabbit, now your up a creek.

  Fuel savings from many of the mods in a small plane are fractional, and then really only seen on aircraft that do a lot of cross country traveling. For the trainers doing touch and gos and the student paying the fuel bill, and banging them up, they arent really worth much.

  In a Bus it could be a different story, especially if they are low cost mods we can do ourselves, and if they actually add some benefit. If a front air dam can give you .5 mpg, and a side benefit is keeping splash water off your windshield, or helping your radiators flow more air, thats a win win. 

[JohnEd]

  We can always count on you for an interesting answer, lol.

Oh, dear.....ohh....It is a Chinese CURSE to wish that someone live in "interesting times".  I wonder that there is no implication for "interesting answers".    Dunno


  The biggest reason there arent more winglets and other aero mods seen in general aviation has more to do with cost than anything. Some of those aftermarket wingtips can cost over $2000, and then you need all that FAA approval and 337's and all that. And the first time come nimrod clips a wing tip on aa hanger door, oh dangnabbit, now your up a creek.

Life's a beotch and then you's dies.  So we need the Gummint to mandate this stuff so economy of scale makes these economic features available to the common man that can afford a private aircraft.  Socialism, I say....cursed socialism.  Saftey and security won't work in this country....like health care, it just so much more interference in my desire to live and "interesting" life without seat belts.

  Fuel savings from many of the mods in a small plane are fractional, and then really only seen on aircraft that do a lot of cross country traveling. For the trainers doing touch and gos and the student paying the fuel bill, and banging them up, they aren't really worth much.

Really serious, if that's possible, sports cars usually advertise a "Drag coefficient" that has nothing to do with gay sex.  The smaller the number, the slippery'er the body design is and the more efficient the car is at going through the air.  Once upon a time the wing struts didn't have those fancy strut to fuselage interface aerodynamic moldings.  At first that was because they didn't know the things would work and they didn't have any anyway.  Then they were known but were not affordable.  Then they were a selling point and "everybody started doing it".  Customer demand for efficiency and SPEED cause a few MPG at cruise sells planes or trains or horses or almost everything.  Lets face it, we are speed demons.  The down turned wing-lets aid in low speed flight control and stall speed and such and they save lives so I can see why they have become a option.....but an expensive one I might imagine.  Not that I know crap about any of this but I am counting on you for an interesting, and not to be overlooked, informed answer.   I remain curious'er and respectfully, yours.

  In a Bus it could be a different story, especially if they are low cost mods we can do ourselves, and if they actually add some benefit. If a front air dam can give you .5 mpg, and a side benefit is keeping splash water off your windshield, or helping your radiators flow more air, that's a win win. 

That's my point.  Costs next to nothing and from then on the benefit is free.  Not to mention talking points explaining how you are helping defeat the Arab menace buy driving a friggen BUS.

Is that what you meant?  Well, is it Pilgrim?  Thanks for the info on airplanes.  i am a big Richard Bach fan.  Me and Johnathan.

John

[babell2]

I noticed that De Havaland up in Canada has had under-turned wing tips since day one for low speed stal and lift things but a Cessna or piper didn't last time I checked. John

I used to work on a Piper Pawnee tow plane that had "Super Drooper" wing tips for better low speed lift and control. Yes it's been around for a while now.

Brice

[JohnEd]

Bryce,

Thank you for that info.  It wasn't me that made the observation about the De Havaland but it makes sense that it was on one of those Puppys that I would have noticed them.

I used to fly on De Havaland Twin Otters from NY to Submarine Base up in Groten, Connecticut.  "Roton Groton" it was called back then.  That was the absolute best darn airplane I have ever flown.  I think it could have taken off with a full load of passengers in a mere 50 yards and do it with only one engine lit off.  Sure it was terribly noisy but you kinda knew it was doing it's job.  Sure it bounced violently all over the sky but that had more to do with the low altitude turbulence and the modest wing loading than any fault of the plane.  The only thing that would have put the whole scene more in character was if the seats were made from Wicker.  Huge high wings with struts and could probably glide like a sail plane....almost.  And brutal beefy fixed landing gear outside my window with the wheels milling over.  I understand they still fly those things all over the world as "Bush Planes".  Justifiably!  Thanks for bringing back that memory.

A friend was putting together a aerial survey plane for prospecting and it had to fly at very low speed safely.  He was one of those "house" EE types and he was a Renaissance man of sorts.  He was designing the winglets and researching wing designs and engines and the electronics and sensor array for geologic work.  Interesting guy and a true engineer/scientist.  Winglets!

Memories, huh?

thanks,

John