Cripes! Another BD-5 Jet down

[MiloMorai]

The Canadiens are still investigating the accident from close to 2 weeks ago.

Actually it is Canadians. If the accident happened in Quebec it would be Canadiens.

[LePaul]

Eh?

[Debonair]

i've never flown a twin...do these planes usually have Vmc a lot higher than Vy?

[Golfer]

i've never flown a twin...do these planes usually have Vmc a lot higher than Vy?

I can't think of any airplane that has a Vmc greater than Vy.  They're usually a comfortable distance apart (larger than 10kt window) but some airplanes they can get pretty tight.

In light twins (piston/ light turboprop) you have a red line and a blue line.  Red line is the published Vmc.  This value is the 'worst case' Vmc.  All the items that the factory are required to meet (i.e. gear up, flaps takeoff, max sea level power on good engine etc etc...) are in this configuration.

Blue line is the best rate of climb on 1 engine.

Vy (two engine best rate) isn't listed on the airpseed indicator but is usually greater than but sometimes equal to blueline.

In jets you have V1, VR, V2, Venr (a cessna thing...if you've never flown a citation you probably haven't heard of it.  Why?  beats me.)

V1 = takeoff decision speed.  Vmc by definition is less than this speed because at V1 you can either takeoff or land in the remaining runway based on altitude/temperature/weight/power setting.

Vr = rotation speed...duuuuuuuuh.

V2 = basically Vxse.  Essentially the best angle of climb on 1 engine.

Venr = enroute climb on 1 engine.  Pretty much the best rate on the single engine, or Vyse.  In the Encore/Ultra it's 160kts all the time.  In Citation II's it varies from 130's to 150's.

[Debonair]

Originally posted by Golfer
...if you've never flown a citation you probably haven't heard of it.  Why?  beats me...

probably cause im still under 300hrs lol
thanks for the info, i was wondering because the MU-2 that crashed near where i fly out of
http://www.ntsb.gov/ntsb/brief.asp?ev_id=20050608X00732&key=1
was, they say, a critical engine out on departure

[Golfer]

The MU2 unfortunately looks great to prospective owners.  You're getting essentially jet performance out of a relatively inexpensive turboprop.

Take some guy who built his business from the ground up with a "can do" attitude who's bullet proof and put him into an airplane that requires perfect technique with an engine out and you're looking for trouble.

People who approach the MU2 with a professional mindset who get the required initial and recurrent training and actually take it seriously rather than something they need to go through are the ones that aren't crashing.

I could fly an M2U perfectly well as long as nothing went wrong.  Without training and doing it a few times with an experienced hand babysitting me...there's a good chance I'd kill myself just like anyone else if I lost a motor at 100' and slow.  The only things I've heard about the MU2 are because it doesn't have ailerons you're required to use rudder as primary bank control which goes against all things natural to me.  Most crashes go something like this:

Joe Pilot Owner or Joe Pilot Lowish time cargo pilot without proper training:

Takes off and flys around a few hundred hours with everything functioning beautifully.  Eventually there's an engine failure that's happening either on takeoff or cruise (which really shouldn't be a big deal)

Takeoff engine failures are the big deals.  You need to use what little excess thrust your good engine is producing to climb at a fraction of your normal rate.  You're low, slow and you're scared enough to really focus on what you're doing.  It's natural to want to bank into the good engine, so you move the stick.  Unfortunately because the airplane has spoilers instead of ailerons you're shooting yourself in the foot.  Why in the world would you want to spoil the lift being produced by this already underpowered airplane?  This slows you down, funks up your control feel and it's where many MU2 drivers have lost it.

A number have also gone in on approaches.  It's a heck of an airplane, looks like its going 300kts on the ground and looks pretty good if I may say so.  It's just a very unforgiving airplane and anything less than a professional or someone who takes a professional attitude toward flying it is on borrowed time.

[Golfer]

Originally posted by Debonair
probably cause im still under 300hrs lol
thanks for the info, i was wondering because the MU-2 that crashed near where i fly out of
http://www.ntsb.gov/ntsb/brief.asp?ev_id=20050608X00732&key=1
was, they say, a critical engine out on departure

And that wasn't a dig at you either.  It's just that Venr is a Cessna thing so was saying why you may or may not have heard of it

[Debonair]

that was just me playing dumb for a joke lol