Redline (inspired by Gross Weight)

[Jose]

So, how far over redline is it "ok" to operate an aircraft, and how
arbitrary is that red line (both on the tach and the airspeed indicator)
and how is it determined?

Jose
--
Nothing takes longer than a shortcut.
for Email, make the obvious change in the address.

[Fred Choate]

hehehe.......and how long could you fly over redline (airspeed) before
structural failure. Yikes....this one could get ugly ;)

Fred


"Jose" > wrote in message
...
> So, how far over redline is it "ok" to operate an aircraft, and how
> arbitrary is that red line (both on the tach and the airspeed indicator)
> and how is it determined?
>
> Jose
> --
> Nothing takes longer than a shortcut.
> for Email, make the obvious change in the address.

[Dave S]

Ask the aircraft and engine manufacturers.

Jose wrote:
> So, how far over redline is it "ok" to operate an aircraft, and how
> arbitrary is that red line (both on the tach and the airspeed indicator)
> and how is it determined?
>
> Jose

[Robert M. Gary]

Jose wrote:
> So, how far over redline is it "ok" to operate an aircraft, and how
> arbitrary is that red line (both on the tach and the airspeed indicator)
> and how is it determined?

Red line airspeed is a pretty specific thing. Unlike yellow line which
is only a problem in turb, red line is the point that things (like
wheel paints) begin to take damage. Red line is not a "if lots of
things happen it will be a problem" its a "something wasn't made strong
enough to do this".

[Peter Duniho]

"Jose" > wrote in message
...
> So, how far over redline is it "ok" to operate an aircraft, and how
> arbitrary is that red line (both on the tach and the airspeed indicator)
> and how is it determined?

Check the engine manual. It will generally give detailed information about
what action(s) need(s) to be taken after exceeding some operational limit
for some amount of time.

For example (an invented example, not necessarily from any actual engine
manual), disasssembly and inspection of the engine if the RPM limit has been
exceeded for more than 5 minutes.

You'll find limits for RPM, temperature, manifold pressure, and possibly
some others.

Pete

[Ben Jackson]

On 2005-07-10, Jose > wrote:
> So, how far over redline is it "ok" to operate an aircraft, and how
> arbitrary is that red line (both on the tach and the airspeed indicator)
> and how is it determined?

Well of course it all depends on how much over gross you are...

--
Ben Jackson
>
http://www.ben.com/

[Matt Whiting]

Jose wrote:

> So, how far over redline is it "ok" to operate an aircraft, and how
> arbitrary is that red line (both on the tach and the airspeed indicator)
> and how is it determined?
>
> Jose

Basically, the same answer as for the "gross" weight question.


Matt

[Kyle Boatright]

"Jose" > wrote in message
...
> So, how far over redline is it "ok" to operate an aircraft, and how
> arbitrary is that red line (both on the tach and the airspeed indicator)
> and how is it determined?
>
> Jose
> --
> Nothing takes longer than a shortcut.
> for Email, make the obvious change in the address.

IIRC, civil aircraft are tested to redline + 10% during the certification
process. That doesn't mean they won't safely fly at redline +11% or more,
but they have only been tested to redline +10%...

[Mike Rapoport]

"Jose" > wrote in message
...
> So, how far over redline is it "ok" to operate an aircraft, and how
> arbitrary is that red line (both on the tach and the airspeed indicator)
> and how is it determined?
>
> Jose
> --
> Nothing takes longer than a shortcut.
> for Email, make the obvious change in the address.

Nobody really knows. Redline on a piston airplane (turbines are different)
is usually set at 90% or Vd which is the highest speed demonstrated in a
dive without flutter or other problems. This is with a new airplane with
new hinges pivots ect.

Mike
MU-2

[Franklin Newton]

Some red lines are only there because of noise (engine PA36-375)
"Mike Rapoport" > wrote in message
k.net...
>
> "Jose" > wrote in message
> ...
> > So, how far over redline is it "ok" to operate an aircraft, and how
> > arbitrary is that red line (both on the tach and the airspeed indicator)
> > and how is it determined?
> >
> > Jose
> > --
> > Nothing takes longer than a shortcut.
> > for Email, make the obvious change in the address.
>
> Nobody really knows. Redline on a piston airplane (turbines are
different)
> is usually set at 90% or Vd which is the highest speed demonstrated in a
> dive without flutter or other problems. This is with a new airplane with
> new hinges pivots ect.
>
> Mike
> MU-2
>
>

[Larry Dighera]

On Sun, 10 Jul 2005 04:31:23 GMT, Jose >
wrote in >::

>So, how far over redline is it "ok" to operate an aircraft, ...

There is a letter to the editor in the current issue of Pilot Getaways
Magazine in which the owner of a Cessna 180 has this to say on the
subject:

Yeah, that is pretty darn fast for an old rust bucket 180 [with a
Vne of 184 mph]. The airplane was fast before I installed some
speed mods and an O-520 replacement engine, so I can't take all
the credit for 195 mph at 2,000 ft MSL. I used to think my
airspeed indicator had a problem until the Cessna 180/185
convention in Spearfish, South Dakota, a couple of years ago (and
the addition of a Garmin 150).

Judging from the responses, I see two questions: (1) How is it
that an old C-180 can do better than Vne, and let alone get into
the yellow arc in the first place? (2) What in the heck are you
doing flying past Vne?

I'll answer question one first. The aircraft has quite a few
speed mods and the engine puts out in excess of 300 hp. Couple
this with the fact that it was a fast airframe to begin with and
you have a fast C-180. The 195 mph has been verified by several
eye witnesses. At 5,000 ft MSL, if you wind the engine up, it
will fly just short of redline (about 165 kts groundsepped on the
GPS with calm winds aloft).

As far as exceeding Vne.... Well, I had to find out how fast it
was, didn't I?

Pete Vinton
Parker, Colorado