ALPHA B-52

[KellyB]

Been flying around in ALPHA's (virtavia) buff, and the autopilot Approach switch does not seem to capture the glide slope. It finds the localizer, ok.

Anyone had any experience with this plane?

Is that how it's supposed to be?

Thanks for any help.

[Motormouse]

Been flying around in ALPHA's (virtavia) buff, and the autopilot Approach switch does not seem to capture the glide slope. It finds the localizer, ok.

Anyone had any experience with this plane?

Is that how it's supposed to be?

Thanks for any help.

You could check aircraft.cfg file, in radios section, check if glideslope is enabled?

Ttfn

Pete

[KellyB]

didn't find anything about glide slopes in the radio section, but discovered these items under autopilot.
If I read it correctly, it looks like the glide slope should be enabled??
I'm referring to the gs_ entries.


[autopilot]
autopilot_available=1
flight_director_available=1
default_vertical_speed=1800.0
autothrottle_available=1
autothrottle_arming_required= 0
autothrottle_max_rpm = 95
autothrottle_takeoff_ga= 1
pitch_takeoff_ga=8 ;
max_pitch=3.0
max_pitch_acceleration=0.20
max_pitch_velocity_lo_alt=0.50
max_pitch_velocity_hi_alt=0.25
max_pitch_velocity_lo_alt_breakpoint=20000.0
max_pitch_velocity_hi_alt_breakpoint=28000.0
max_bank=25.0
max_bank_acceleration=1.8
max_bank_velocity=3.00
max_throttle_rate=0.10
nav_proportional_control=11.00
nav_integrator_control=0.17
nav_derivative_control=0.00
nav_integrator_boundary=2.50
nav_derivative_boundary=0.00
gs_proportional_control=19.0
gs_integrator_control=0.530
gs_derivative_control=0.00
gs_integrator_boundary=0.70
gs_derivative_boundary=0.00
yaw_damper_gain = 1.0

[Tom Clayton]

The Radio section doesn't spell out the glideslope availability every time, so I'll show you what to look for. This is the section from the stock C172 with a few things color coded and highlighted:

[Radios]
// Radio Type = availiable, standby frequency, has glide slope
Audio.1 = 1
Com.1 = 1, 1
Com.2 = 1, 1
Nav.1 = 1, 1, 1
Nav.2 = 1, 1, 0
Adf.1 = 1
Transponder.1 = 1
Marker.1 = 1

The ones and zeroes are a toggle indicator - yes or no. The blue column indicates whether the radio gauge operates with a standby frequency like the Cessnas, or without, like the King Air. The red column indicates whether the receiver will pick up a glide slope. In almost every instance, you want Nav.1 to have a "1" in that third column. If Nav.2 has it as well, that's fine, but most autopilots only work with Nav.1 radios.

[KellyB]

Thanks to both of you.

I find that everything points to the autopilot and nav1 radio having glide slope capture capability.
It seems to capture the slope initially, but does not follow it correctly down to decision altitude as other AP's do.

It is probably my technique. I've not run into an aircraft that asks for spoiler deployment on approach in addition to high flap settings. I'll keep mucking about till I get it.

Incidentally, I thought incremental deployment of spoilers wasn't possible in fs9, but seems to work with this AC.

[Sunny9850]

I have not looked at the BUFF but if all the settings in the radio section are looking correct you might want to experiment with these in the autopilot section by comparing them to for example the default 747.

gs_proportional_control=19.0
gs_integrator_control=0.530
gs_derivative_control=0.00
gs_integrator_boundary=0.70
gs_derivative_boundary=0.00

Stefan

[Tom Clayton]

Incidentally, I thought incremental deployment of spoilers wasn't possible in fs9, but seems to work with this AC.

If you have a controller like the X-52 with tons of rotaries and slides, you can assign one to the spoiler function via the assignments menu. Just be sure to test before flying to make sure you don't need to check the reverse option.

[nater]

Tom is right. I have my spoilers mapped to the slider on the X52's throttle. By doing that I can give incremental spoiler settings.

[pfflyers]

I've owned the ALPHA B-52 for years, but must confess I never flew it much. After reading this thread I decided to see if I could get it to fly an ILS. Turns out I experienced the same thing as KellyB, it would follow the localizer but not the glideslope. I took the KBT B-52 on the same circuit and it flew the ILS just fine. So I copied the autopilot section of the KBT config into the ALPHA config, didn't work. Then I installed the autopilot gauge from the KBT panel into the ALPHA panel, still didn't work. Finally I copied the airfile from the KBT into the ALPHA folder, retained the original ALPHA config file, just edited it to point to the KBT airfile and it flew the ILS just fine. I don't know anything about airfiles, never opened or edited one, so I don't know what would be in the airfile that would control whether an aircraft will track a glideslope or not. So I guess I "fixed" it, but I'm not sure this is the right answer.

[KellyB]

I've owned the ALPHA B-52 for years, but must confess I never flew it much. After reading this thread I decided to see if I could get it to fly an ILS. Turns out I experienced the same thing as KellyB, it would follow the localizer but not the glideslope. I took the KBT B-52 on the same circuit and it flew the ILS just fine. So I copied the autopilot section of the KBT config into the ALPHA config, didn't work. Then I installed the autopilot gauge from the KBT panel into the ALPHA panel, still didn't work. Finally I copied the airfile from the KBT into the ALPHA folder, retained the original ALPHA config file, just edited it to point to the KBT airfile and it flew the ILS just fine. I don't know anything about airfiles, never opened or edited one, so I don't know what would be in the airfile that would control whether an aircraft will track a glideslope or not. So I guess I "fixed" it, but I'm not sure this is the right answer.

Glad to know it's not just me; I can't find the KBT buff, so I'll muck about with another ils follower i know works.

@Tom: I fiddled with the air file for the stock fs9 Boeing 737-400, and unticked the auto spoiler box and I can set spoilers incrementally with the mouse. I have the Saitek EVO with only the one slider for the throttle, so can't assign a slider. I got te idea from peeking inside the B-52 airfile, and noticed that the auto spoiler box was unchecked.

Again to everyone, thanks for the input! Great site as always.

[Bill Kestell]

Well ... how about this:

Anyone else notice that the BUFF flys "nose down"? Is this actually the attitude it should cruise at? If not, what aspects of the Air CFG file need to be changed in order to have it cruise at level attitude?

(Just makes ma crazy when I'm off on either port or starboard looking at the aircraft ... looks WIERD.:isadizzy:

[srgalahad]

Well ... how about this:

Anyone else notice that the BUFF flys "nose down"? Is this actually the attitude it should cruise at? If not, what aspects of the Air CFG file need to be changed in order to have it cruise at level attitude?
(Just makes ma crazy when I'm off on either port or starboard looking at the aircraft ... looks WIERD.:isadizzy:

There have been a couple of threads in the past discussing this, but simply, yes. The B-52 can't "rotate" in the conventional sense, so the wing incidence is set to give a positive AOA at takeoff with all main gear on the runway. It also climbs "flat", or nearly so and therefore will be nose-down in level flight. Remember, it's not the fuselage that 'flies' but the wings so it is their attitude that is relevant.

[Motormouse]

Glad to know it's not just me; I can't find the KBT buff

Here you go , flightsim.com

Name: b52dgh_x.zip
Size: 31,401,615 Date: 12-19-2004 Downloads: 15,314


FS2002/FS2004 Boeing B-52H Stratofortress full package. Includes B-52H, B-52D, XB-52, X-38, B-52G and X-15. By Yaetsu Yoshimitsu and Hiroaki Kubota (KBT Japan). Recommended panel is B52KM_PA.ZIP

and

Name: 52fullup.zip
Size: 11,467,589 Date: 09-17-2004 Downloads: 11,832


FS2002/FS2004 Boeing B-52 Stratofortress. Includes five popular variations of the B-52G and B-52D. Update version that now supports both FS2002 and FS2004. Gmax model by Yaetsu Yoshimitsu. Flight dynamics by Hiroaki Kubota

ttfn

Pete

[pfflyers]

Pete, thanks for posting the links for the KBT models. I highly recommend them to any BUFF fans out there. They cover the entire life cycle of the B-52 including the NASA motherships. IIRC the original download does not include a panel, I adapted the 2d ones from the ALPHA pack for mine. There is no vc, but they are suitable for use as AI and there's even an AI airfile included in the download.

[Tom Clayton]

Glad it's getting straight! As for the BUFF's flight attitude, I've seen them take off tail first - it's a strange thing to see the first time!

If you want to edit air files, you'll need an editor. I like this one:

FS2004 (ACOF) - Misc.FS2004/FSX Aircraft Airfile Manager V2.2
[ Download | View ]
Name: aamv22.zip
Size: 1,553,886 Date: 09-27-2009 Downloads: 4,024



Aircraft Airfile Manager V2.2. AAM lets you view and change .air files within FSX, FS2004 and earlier, and MS Combat Flight Simulator. V2.2 fixes a bug that caused an empty aircraft list. By Karl-Heinz Klotz.

[Bill Kestell]

Thanks ... strange, but if that's how they fly, THAT'S HOW THEY FLY.