Baron-fde-fix possible?

[Wells 5]

On 10/10/2018 at 7:53 AM, Milviz said:

That would be Wells Sullivan.  Very good and a canadian to boot.

That would be me.  I love the twin comanche.  It was/is a pleasure to research and make this airplane fly according to what aerodynamics/physics predicts and to match pilot accounts of flying it.  Our beta testers seemed quite pleased with it.  Of course, we will continue to support it and correct any problems as they occur.  On that note, I am willing to review the B55 as well.

[scottb613 1,188]

10 hours ago, wells said:

That would be me.  I love the twin comanche.  It was/is a pleasure to research and make this airplane fly according to what aerodynamics/physics predicts and to match pilot accounts of flying it.  Our beta testers seemed quite pleased with it.  Of course, we will continue to support it and correct any problems as they occur.  On that note, I am willing to review the B55 as well.

Hi Wells,

Thanks for introducing yourself - I've always been very interested in FDE work and I've even dabbled myself on occasion - enough to know it's some arcane science that requires a blood sacrifice of some chickens - a masters degree in aeronautical engineering - and - a gamblers luck - to get it right... I've chatted with most of the known FDE guys at some point...

If you're serious about the B55 - it's truly a beautiful model and worthy - I'd be happy to help out anyway I can... Bottom line - I think the cruise speed was off a bit - but the real issue becomes evident when you try to fly an approach... If you fly the correct approach speed with the correct sight picture (deck angle) - you're dropping like a stone at 1500 FPM or more... If you attempt to arrest the descent rate for a proper approach you're looking at nothing but sky... Of course this can all be fixed by increasing your approach speed well beyond book values and it masks the issues... It's been years since I've flown it due to the FDE problems it had - so I'm just going from recollection at this point...

I've chatted with Bernt Stolle in the past regarding this topic - who was one of the guys who worked on the FDE initially and he said this FDE was a kludge for whatever reason and a few people had their hands in it - but it was never finished to his satisfaction and he made no claim to this FDE being his work...

That said I have the full POH on the B55 and would gladly share it with you if this is a road you choose to go down... Just PM me...

Thanks...

Regards,

Scott   

Edited October 29, 2018 by scottb613

[Wells 5]

I know from researching Beechcraft airplanes in the past, that they do not provide as much information as other manufacturers do, with regard to aerodynamic particulars, and so it is understandable that it would be more difficult to make a flight model for such an airplane.  Also, it has been several years now, and there are perhaps more resources available online than there were back then.  I did fly it and I see what you mean.  I was able to find the POH and service manuals.  There are two things to look at,

1.  Viewpoint - I was able to improve forward vision by just raising the viewpoint a little bit

2.  The zero lift angle needs to be verified, given the incidence, airfoil sections and twist/washout of the wing design

[FDEdev 955]

12 hours ago, wells said:

The zero lift angle needs to be verified, given the incidence, airfoil sections and twist/washout of the wing design

Another problem is, even if you know the root (NACA 23016.5 +4°) & tip (NACA 23012 +1°) incidence and if it's a geometric and/or aerodynamic washout, where along the span these changes occur. 

Furthermore it's important to note that the Milviz B55 and the E55 have been designed by different FDE designers and the E55 uses different airfoils with different incident angles. (Bernt didn't work on the B55 FDE AFAIK)

 

Edited October 30, 2018 by FDEdev

[scottb613 1,188]

Hi Folks,

Nice to see active interest in this old classic... Honestly - if we don't fix this one we will probably never see another B55 in FS - as it's somewhat more obscure than say the 58 model... LOL - I guess my interest is - it would be a far more attainable goal for a pilot to aspire to vs than say the multi million dollar G58 - lol - helps with the immersion for me... The VC was beautiful in this model and far prettier than the utilitarian C310 VC...

Oh - thanks for the clarification of the FDE modelers - maybe I had them backwards - I had the conversation long ago and my recollection can be less than perfect - LOL... The E55 FDE isn't really applicable here - so I'm not sure why MilViz included it - as the model is definitely that of the B model 55... The E model 55 has air intakes on top of the engine nacelles much like the B58 - that this model is lacking... MilViz has already stated any prospective update to the model would eliminate the E model FDE altogether... I really didn't test the E model FDE extensively...

So - yeah - I'm not a twin pilot although I have operated the controls a few times on a Duchess - under supervision... I believe most light twin pilots fly approaches on the blue line or best single engine climb rate marker... I forget where that is on this bird and I don't have access to my PC at the moment - 1.3 * Vs0 works out to about 85 Knots IIRC... That said - I really don't think the aircraft should have that tendency to want to sit back on it's haunches at any point down to Vs0... It's like the center of lift is too far forwards (layman's terms) - I watched countless videos of B55's while testing back when I purchased this model and noticed the problems - none appeared to pitch up on approach... While the viewpoint may have exacerbated the issue - I recorded many of my approaches while testing and the model definitely pitched up as well...

I'm really glad someone could recreate the issue I noticed... Thanks for taking the time...

I don't have the B55 v4 update - unfortunately I believe I bought the aircraft from that Australian reseller that has gone MIA recently - is there anyway I can update my model to v4 from MilViz - that way we can be on the same page while discussing it ?

Again folks - appreciate the interest...

Regards,

Scott

 

Edited October 30, 2018 by scottb613

[FDEdev 955]

1 hour ago, scottb613 said:

I believe most light twin pilots fly approaches on the blue line or best single engine climb rate marker... I forget where that is on this bird and I don't have access to my PC at the moment - 1.3 * Vs0 works out to about 85 Knots IIRC...

V_YSE =101kias. V_REF 90kias V_ST0 = 74kias    This is interesting because V_ST0 x 1.3 = 96kts which means V_REF is really low.

If you fly the approach at V_YSE you have to make sure that you start reducing the speed early enough, so that you don't compromise the landing and/or go around performance!  

Edited October 30, 2018 by FDEdev

[scottb613 1,188]

Hi...

Thanks for the additional info - mate... Yeah - that does seem odd that Vref is so much lower than 96 Knots...

Regards,
Scott

Edited October 30, 2018 by scottb613

[FDEdev 955]

Found the solution. The POH mentions that the stall speed decreases by 4kts at a zero thrust condition. In this case the 90kts are valid.

It seems to be vital to know that if you are too high in a B55 and at the correct approach speed, that you have to increase the airspeed first and afterwards you can close the throttles.

Edited October 30, 2018 by FDEdev

[scottb613 1,188]

39 minutes ago, FDEdev said:

Found the solution. The POH mentions that the stall speed decreases by 4kts at a zero thrust condition. In this case the 90kts are valid.

It seems to be vital to know that if you are too high in a B55 and at the correct approach speed, that you have to increase the airspeed first and afterwards you can close the throttles.

Hi FDE...

Hah - thanks so much for following up on this... Seems counterintuitive - I wonder how many real Baron pilots miss that tidbit ?

Regards,
Scott 

[Wells 5]

14 hours ago, scottb613 said:

 

I don't have the B55 v4 update - unfortunately I believe I bought the aircraft from that Australian reseller that has gone MIA recently - is there anyway I can update my model to v4 from MilViz - that way we can be on the same page while discussing it ?

Again folks - appreciate the interest...

Regards,

Scott

 

Hi Scott,

The update to v4 is available from the Milviz support forum for the B55.  That is also where the FDE update will be posted in the not too distant future.

[scottb613 1,188]

Hi Wells,

Thanks so much - really - I'm sure there is an old post of mine in that support forum as well... I'll look for the v4 update this weekend when I get in... Truly appreciate your interest...

Hi Colin,

Roger that - will do...

Regards,
Scott

Edited October 31, 2018 by scottb613

[scottb613 1,188]

Hi Folks,

We've been chatting about an FDE problem - in a Comanche thread - that has been inherent in the B55 Baron since I've purchased it and prevented me from enjoying it... Honestly - it's been shelved for years on my system... "Wells Sullivan" - MilViz's current FDE guy - kindly offered to take a look at it... He actually sees the same problem I've reported and stated he's working on an update... Makes me pretty happy as I really like the model, VC, and sound set on their product...

If you've noticed any other anomalies in the FDE - I'd suggest this is the time to mention it since he's looking at it now...

 

This was my description of the FDE issue which I've espoused on multiple occasions:

Quote

If you're serious about the B55 - it's truly a beautiful model and worthy - I'd be happy to help out anyway I can... Bottom line - I think the cruise speed was off a bit - but the real issue becomes evident when you try to fly an approach... If you fly the correct approach speed with the correct sight picture (deck angle) - you're dropping like a stone at 1500 FPM or more... If you attempt to arrest the descent rate for a proper approach you're looking at nothing but sky... Of course this can all be fixed by increasing your approach speed well beyond book values and it masks the issues... It's been years since I've flown it due to the FDE problems it had - so I'm just going from recollection at this point...   

 

Thank you again - Wells - much appreciated - sir...

Regards,

Scott

Edited October 31, 2018 by scottb613

[tttocs 301]

Really pleased to see this discussion taking place, and getting such positive response.  Thanks Scott for bringing this up, and to the Milviz team for being so receptive.  Well done!

Scott

[Wells 5]

An update has been posted in the Milviz B55 support forum.  If you don't have access, contact Oisin and he'll hook you up!

Changes

- Corrected weight and balance for 6 seat configuration

- Corrected engine power output and fuel consumption for given power setting ( power and fuel consumption were high )

- Corrected cruise speeds for a given power setting ( the airplane was 5-10 knots fast )

 - Changed the zero lift angle of the wing by 1° and raised the viewpoint by 1.2 inches

- Added a bunch of extra internal and external views

[scottb613 1,188]

8 hours ago, wells said:

An update has been posted in the Milviz B55 support forum.  If you don't have access, contact Oisin and he'll hook you up!

Hi Wells,

I do have an account over there - I'll see if I can get the Baron loaded up again over the weekend - patched for v4 - then load your new FDE...

Truly looking forward to trying it...

Thanks so much for your time and effort - I'll provide feedback...

 

Hi Folks,

If anyone gets the chance to try this before me - please post feedback...

 

Regards,
Scott

Edited November 2, 2018 by scottb613