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Overspeed

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EHM-1703 Philip:
Thanks Bruce,

That is probably the best tip anyone has given, keep your aircraft well inside the envelope of its design performance. Check and keep to the long range cruise speed of your aircraft and you should remain safe. For instance, when flying the 738 I keep my cruise speed to M.76 which gives enough of a buffer to allow for all eventualities. (Overspeed occurs at M.82 so normally any possible problems are picked up by the AT)

Below is a list of long range cruise speeds for our main division jets taken from the fleet pages. If you stay within or 1 click less than these speeds you should not suffer the problem.

F70 - M.70
E170 - M.70
A322 - M.75
B738 - M.76
A333 - M.82
B763 - M.80
A345 - M.83
B744 - M.85

I have suffered this problem myself in the past and it was because I was topping my PMDG738 out at M.78 which is too close to its performance limits. Like Bruce, I don't have the problem anymore unless I am pressing on to avoid traffic conflicts! (Normally when I have Bruno coming up behind me during a fly in!!! :) )

EHM-0948 Bruno:
Hi,

PHilip please also what altitude are those Mach values ? Because the mach speed vs ground speed differs at different altitudes.
I suggest you are around FL330 right ?

EHM-1703 Philip:
Bruno,

Now you will have to forgive me, I am not a physisist so my explanation here will wander and may be faulted but as I understand it......

Air stress tolerances are not measured by GS, Mach speed, KIAS or TAS. They are measured by EAS or the planes Equivelant Airspeed. This is the equivelant speed on a standard day at sea level. There is a relationship between EAS and the Mach speed and there is quite a complex calculation involved to work this out.

Mach measurements are calculated using a static pressure measurement, an impact pressure measurement and also using the speed of sound as a constant, so therefore regardless of altitude or pressure, a Boeing 738 should be able to withstand  the stresses involved in flying at M.80 at sea level on a "standard" (standard pressure and no wind component) day.... the only problem is..... It does not have the power to do so and would need to exceed these stress tolerances to dive in to this situation therefore it is almost a physical impossibility to achieve it. (I think!)

So with this in mind and with regards to my initial comment above, the maximum mach speed or for that matter the recommended long range cruise speed will never change, regardless of altitude, wind or pressure. At lower altitudes or in strong head winds this figure may not be achievable although at higher altitudes and with strong tailwinds it is easily possible to exceed them.

As I said, I am no scientist and I am open to correction, this is merely my limited understanding of flight dynamics so I hope I made myself a little clearer.

EHM-1714 João:
I'm sad to see nothing has changed with ProPilot. Adding two lines of code would do wonders for that program.
Once again, after 10 hours of flight and while cruising I had an overspeed penalty and the reason? Weather update from IVAO... It's not that I don't agree with that penalty existing, but I just think something can and should be changed so that it doesn't show up when it shouldn't.
Another thing, some days ago I flew a 2 hours flight with PP and when submitting the flight I got a message saying that it couldn't be recorded as a ProPilot flight since I wasn't connected to the internet. Although I was connect, I'm going to assume something went wrong with my connection, but I can't stop but wonder why the flight information can't be recorded locally on the user's computer and then submitted to the website.
I'm a fan of ProPilot and I believe it has great potential, but I think there's still a long way for improvement and the way the program is right now it's just not accurate enough.

João

EHM-1703 Philip:
João

Sorry you are having trouble, as you said, PP is not perfect and to be honest, I think it will always have faults as not every bodies system and FS setup can be accounted for and we do not have the ability to put thousands of man hours in to its development as some payware producers can do.

Unfortunately, we really can not alter the way FS interprets weather information from IVAO. The only way for us to combat this would be to pay the fee to Pete Dowson to register the Flight Logger with FSUIPC and use the wind smoothing function, this is really not something we can afford to do. (in fact it would be far cheaper for you to register your personal copy of FSUIPC and then enable the wind smoothing feature!)

Can I just check you have enabled wind smoothing in your IvAp settings? (on a standard clean install it is located under - Start>All Programs>IVAO>IvAp-IVAO Virtual Pilot Client>IvAp Configuration) You can click on the weather tab and enable a certain amount of wind smoothing from there although it is not controllable, to do this you have to register FSUIPC.

Andrei will be working on a connection light and/or messaging system on the next version of the Flight Logger to try and iron out the connection problem but this is a long way off as the program is having to be re-written from scratch! It will take a while as he can not work on it full time as he has a real life too! Please remember, ProPilot is still a freeware product that is available to all our pilots which is something no other VA offers, yes it's not perfect but we can not compete with the likes of payware products such as FS passengers because we want to keep it free.

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