Hello community,
I want to ask: How is realism and performance?



my system: Core i7 920, 260 GTX, 8GB RAM

It performs very well on my system (see my signature below). As for realism, I've never been a real B-52 driver to be able to answer that. I think it is great and I love flying it.

Mark

I bought the plane last night and only flown a few flights but....

1st take off I began a steep climbout and looked down to tinker with the autopilot. I glance up worried about stalling out but instead was doing close to 500 knots and accelerating through 20 thousand feet  :P
I level flight I have to pull the throttles almost to zero to keep the plane from overspeeding and still it maintains over 400 knots. I have since rebooted and going to fly some more today but having fighter like acceleration and climb is not what I expected from this behemoth.
My initial observations on computer performance is that the b-52 is tough on frames. I am running a i7,5870 and the buff is putting a hurting on my frames. Again I need to spend some more time today before any final judgements.

RIPPDOFF wrote on Dec 12^th, 2010 at 4:48pm:

... I began a steep climbout and looked down to tinker with the autopilot. I glance up worried about stalling out but instead was doing close to 500 knots and accelerating through 20 thousand feet. In level flight I have to pull the throttles almost to zero to keep the plane from overspeeding and still it maintains over 400 knots. judgements.

The B-52 Driver does seem to have an awful lot of power?
Flys more like a small business jet than a large bomber.

It also flys and takes off with the nose up?

I'm not a pilot but I watched plenty of B-52s fly while in the USAF,
and they all had a slightly nose down (or closer to level) attitude while flying.

I've not noticed any FPS problems.

It's still worth every penny!
I'm glad I bought it!

I have only flown a few flights and with a 30% load. So maybe I will try a heavier load and see how she handles. I know its tough to balance betreen the actual power needed yet keep the speed and acceleration realistic.
I am currently fighting with learning the autopilot. I am assuming you cannot turn the heading bug and have the ap track it. If so I am yet to figure it out. I added a gps and the ap will follow whatever I have in the gps. The ap trim thingie in the center console is useless for me. It does not seem to want to move when clicked or turned but when it does it does not want to stop. I plan to fly some more tonight and try and see if its the plane or me. Who know I may actually read the manual. :P

RIPPDOFF wrote on Dec 12^th, 2010 at 7:39pm:

.... I am assuming you cannot turn the heading bug and have the ap track it. If so I am yet to figure it out.

Check page 47, Part II, Aircraft and Systems manual.

Heading Selector Switch
In MAN (manual) position, the flight director system will override Nav Mode Selector Switch.
The bank steering bar will respond to the heading set by the heading set knob on the captain's horizontal situation indicator.

Thanks for the reply but Nada,nothing. I think I have tried every combination and only alt hold works. Now this is from the default start flight engines running. I simply flip on the pilot on switch which also turns the servos on. Next to that is the mode select, Heading select man or norm and "inst" control. Not to many combinations so I must have stumbled across the right one by now. Still the heading bug has no effect.

At a 30% load, roughly, I takeoff with full throttles. After I get airborne, I press "Z" to get the A/P on and holding a not too steep of a climb. I then pull the throttles back to about 70%-75% or the B-52 will reach 400+ knots. I then use the A/P trim wheels to get to about a 4000 feet per minute climb. I may have to reduce the throttles further to stop from overspeeding. At that weight the B-52 can easily reach FL400 and I reduce the throttles to 60% which I have found is just enough to keep it from overspeeding (regardless of its weight). For the percentage readings on the throttles, I have "Show cockpit ToolTips" turned ON (checked) in Options > Settings > Display > Aircraft.

Mark

jbntx wrote on Dec 12^th, 2010 at 5:40pm:

The B-52 Driver does seem to have an awful lot of power? Flys more like a small business jet than a large bomber. It also flys and takes off with the nose up? I'm not a pilot but I watched plenty of B-52s fly while in the USAF, and they all had a slightly nose down (or closer to level) attitude while flying. I've not noticed any FPS problems. It's still worth every penny! I'm glad I bought it!

Yes the FDE is my only complaint on this BUFF, they most certainly take off horizon level or as you said even a bit nose down.  I wonder if they've put too much power into those 8 turbines.

The static_thrust, is entry in the aircraft.cfg for the engine power. Aircraft in FSX can have a maximum of four engines.

Captain Sim have the setting at 30000 (30000 / 2 = 15000) so that equates to 15000 lbs of thrust for each engine. See the bold lettering below.

[TurbineEngineData]
fuel_flow_gain          = 0.002                 //Gain on fuel flow
inlet_area              = 17.0                  //Square Feet, engine nacelle inlet area
rated_N2_rpm            = 29920                 //RPM, second stage compressor rated value
static_thrust           = 30000                        //Lbs, max rated static thrust at Sea Level
afterburner_available   = 0                     //Afterburner available?
reverser_available      = 0                     //Thrust reverser available?
ThrustSpecificFuelConsumption = 0.40

According to Wikipedia (I know it isn't the best source of information, but it will do): Powerplant: 8× Pratt & Whitney TF33-P-3/103 turbofans, 17,000 lbf (76 kN) each. So you can see that Captain Sim have set each of the engines at less power.

Captain Sim could provide a more detailed answer than mine. Let's hope they do.

Mark

Howdy,

Computer performance-  great, not a problem at all.
Flight Deck realism - awesome, If Captain Sim could box smells you wouldn't know you were really at home.

Aircraft FDE performance: It taxi's quite well, and flies like a half full bathtub with 8 PW4000's pushing. The bathtub part is right on the money, the PW4000’s are not. Currently she climbs like a homesick angel and races for 400kts so quick it is hard to manage, even with the throttles way back. I finally have the 'H-1-1. The TF-33P-3 produces about 14,550lbs of thrust a standard day, for an aircraft total of 116400lbs. The acft.cfg has thrust as 30,000 per pair for 120,000lbs total, which matches the .air file. I don’t think 4,000lbs of thrust should make such an extreme difference, I believe it is an under-drag issue going on here.

The CG and fuel tank positions also need some tweaking. Currently the .air file is showing a CG range of 49 to 51% MAC, this should be 18 to 34% MAC, which would explain the nose up pitch on takeoff and landing.

The systems all work very well (this is a Fun Line Aircraft). Although the Flight Engineer in me craves more, there is plenty enough complexity to satisfy. I'm still trying to decipher the correct fuel usage sequence and valve setup, there are a few missing flow lines and labels on the fuel panel. I would also highly recommend either setting the acft.cfg for battery always available or extending the battery life with FSUIPC.

The Normal procedures are currently useable, but need a few corrections for redundancy and actual model characteristics.

Overall- I HIGHLY recommend this aircraft, it is a pleasure to fly and bestows great credit to the mighty BUFF.

--Dan

I've altered the thrust value from 30000 down to 22000 and it performs better now, meaning not like a rocket.

Remember, "fun" could very well mean "always enough thrust" so I don't blame the devs for setting up this value together with a very low drag component on this plane.

I did some calculations over at Avsim (maybe Mark refers to them, I don't know) and from the pure thrust setting in the config, we are underpowered.
But, as said, nobody knows how the drag is calculated here and everybody surely will have experienced the unnatural high performance of this big bird even on high loads.
I very much join in with HvyEng, the drag component would be the one to look at. But as the thrust change can easily be done by any user, I'd say that a current workaround (unless you need the extra performance) should be based on this value.

So to counteract, an even lower thrust can be recommended.
Fuel Flow therefor rises a bit and gives you lesser range, but as some guys have already tested, range isn't a problem with the default 30000 value. With 22000 it might get closer to real values.

EPR values and even EGT aren't things to watch closely here, they belong to the default FSX engine model and therefor show "some" values, not accurate ones. N1 seems better to roughly estimate power output.
But, hey, talking about a fun product with a very nice price point and great atmosphere here, so enjoy it.

HvyEng wrote on Dec 13^th, 2010 at 4:53pm:

I would also highly recommend either setting the acft.cfg for battery always available or extending the battery life with FSUIPC.

I have not had any problem with power going off if the aircraft was sitting idle (power turn on and engines not running) for quite some time. I don't have the increased battery power checked in FSUIPC either.

I did notice this though. I turned the Avionics OFF on a different aircraft that I had been flying before switching to the BUFF. It took me a few minutes to figure out why the FD switch would NOT stay on when I switched it ON (at all other times it stayed on like it should). This means that:
1. You need to tie the Avionics switch to a short cut key combination (mine CTRL+SHIFT+A) so you can turn them on if they are OFF.
2. Make sure the default Free Flight flight has the Avionics Switch ON (this is the recommendation for most Add-on aircraft).

I'm seriously thinking of doing what CoolP has done. Change the power from 30000 to 22000 tp try it out. But first I'm going to uninstall the B-52 Driver and re-install the B-52 BUFF Exterior and then save the aircraft.cfg before "upgrading" to the B-52 Driver again, so I can compare them. I'll report back on the engine power rating that it had.

Mark

I uninstalled the B-52 Driver and reinstalled the B-52 BUFF Exterior. Grabbed the aircraft.cfg and then re-installed the B-52 Driver.

Here is what I found with regards to the GeneralEngineData and TurbineEngineData:

[GeneralEngineData]
engine_type = 1                                 //0=Piston, 1=Jet, 2=None, 3=Helo-Turbine, 4=Rocket, 5=Turboprop
Engine.0 =  20, -60, -10
Engine.1 =   0, -34, -8
Engine.2 =   0,  34, -8
Engine.3 =  20,  60, -10
fuel_flow_scalar   = 0.60   ------------->      fuel_flow_scalar   = 1.0        //Scalar for fuel flow efficiency    
min_throttle_limit = -0.50; ------------->      min_throttle_limit = -0.25;     //Minimum percent throttle.  Generally negative for turbine reverser

[TurbineEngineData]
fuel_flow_gain          = 0.002
inlet_area              = 17.0   -------->      inlet_area              = 24.0  //Square Feet, engine nacelle inlet area
rated_N2_rpm            = 29920
static_thrust           = 30000       -------->      static_thrust           = 34000 //Lbs, max rated static thrust at Sea Level
afterburner_available   = 0
reverser_available      = 0      -------->      reverser_available      = 1     //Thrust reverser available?
ThrustSpecificFuelConsumption = 0.40

The blue text is taken from the B-52 Buff Exterior's aircraft.cfg. By all rights, the Exterior should outperformed the Driver. Unless the inlet_area + the static_thrust are combined in some way? I'm just not that good with this section of the aircraft configuration files.

It could be worth changing the fuel_flow_scalar to 1.0, the setting that the Exterior had, instead of the 0.60 that it is in the Driver. I flew, with full tanks, from Guam to Hanoi then went on to land at Saigon. It was 3008+ nm and I used 21% of my fuel (had a very heavy landing because I was over Max Landing Weight). I figured that with that fuel consumption rate I could fly for 14000nm, or more, which I think is close to twice it Maximum Range. With the setting of 0.60 compared to 1.0 would make the Max Range sound right. The downside to changing that is that usually when I increase the fuel_flow_scalar the aircrafts engine power increases with it.

Mark

yeah, I would love to tweak a lot of these, but wouldn't changing these also invalidate the manual? Wouldn't their charts and climb power graphs and all that become useless? Or are they all real, and changing these settings will actually make them closer to how the B-52 Driver flies?

I also remember the B-52 being able to climb up to like FL500, and I can't with the driver.

Off-Topic replies have been moved to this Topic.

TurbofanDude wrote on Dec 14^th, 2010 at 2:51pm:

yeah, I would love to tweak a lot of these, but wouldn't changing these also invalidate the manual? Wouldn't their charts and climb power graphs and all that become useless? Or are they all real, and changing these settings will actually make them closer to how the B-52 Driver flies?

As far as I know, their charts and graphs on B-52's performance are from real manuals, so I can't see how you could invalidate them by tweaking the aircraft.cfg. We are just trying things out so it is closer to the "real thing". ;)

Mark

jbntx wrote on Dec 12^th, 2010 at 5:40pm:

[quote author=RIPPDOFF link=1292161490/0#2 date=1292172531] ... It also flys and takes off with the nose up? I'm not a pilot but I watched plenty of B-52s fly while in the USAF, and they all had a slightly nose down (or closer to level) attitude while flying. It's still worth every penny! I'm glad I bought it!

Shifting the center of lift forward would correct this. As a workaround, I enter the pilot and copilot weights as several thousand pounds each. This moves the CG forward, and, if I set stab trim properly she lifts off with very little pitch.

[quote author=jbntx link=1292161490/0#3 date=1292175655][quote author=RIPPDOFF link=1292161490/0#2 date=1292172531]

It also flys and takes off with the nose up?

I'm not a pilot but I watched plenty of B-52s fly while in the USAF,
and they all had a slightly nose down (or closer to level) attitude while flying.

You probably saw the BUFs in the traffic pattern, at the end of the mission, when all the body tank fuel except forward body ballast had been consumed and only fuel in the main tanks was left. The plane flies nose-low at that stage of flight, and if you're not careful, you can get a nose gear touching down first---starts a really sporty "porpoising" action... :P

TurbofanDude wrote on Dec 14^th, 2010 at 2:56pm:

I also remember the B-52 being able to climb up to like FL500, and I can't with the driver.

A test flight once took a B-52 to 50K feet, but it was specially configured and the crew wore partial pressure suits. I had one at 43,000 once, and it was darned uncomfortable..pressure breathing sucks!