Landing wheelie bug report.

[Jet_Pack2 0]

13 minutes ago, ph-cxz said:

Because you turned off the flight director you can’t read the fma which tells you your speed information. Secondly you are flaring too high only a 2 degree nose up in necessary.

I actually found a screenshot from the approach (how do I upload it?), the FDs are off but the FMA still showed SPD. It might have been a graphical artefact.
My video didn't really start at my flare, that was after the second or third bounce and I was not actively pitching down, I had to let go of the controls to start the recording.
Approach speed was only 130kts, yellow line stated at 118kts, red line at 102kts. Pitch during the approach was 6 degrees, stall indicator was shown at roughly 13 degrees, so there was still a bit of room to a stall. But might have been a bit too nose up... This wasn't a well planned flight, I didn't even enter a gross weight into the FMC fields before departure, so I was lucky to have any stall speeds at all.

Edited December 15, 2018 by Jet_Pack2

[downscc 1,327]

15 minutes ago, Jet_Pack2 said:

Pitch during the approach was 6 degrees, stall indicator was shown at roughly 13 degrees, so there was still a bit of room to a stall.

Makes no difference, if approach was 6 degrees NU your flare should not have been any more rotation than 8-9 deg NU.  If you over flare you will significantly increase your landing distance even if there's no problem with the rolling resistance.

[Jet_Pack2 0]

20 hours ago, downscc said:

Makes no difference, if approach was 6 degrees NU your flare should not have been any more rotation than 8-9 deg NU.  If you over flare you will significantly increase your landing distance even if there's no problem with the rolling resistance.

That's all good but I never recorded my pitch during the flare, so even I don't know what my pitch angle was before or during the flare (my video did not show my actual flare). I know my first touch down was right in the touch down zone and very smooth, the long landing was only caused by the landing gear glitch giving me an extra 5 to 10kt boost upon touch down.

[berts 97]

On 10/30/2018 at 7:53 AM, Qavion2 said:

Did you accidentally activate Pogo Stick power after you turned off the engines ?? 🤔

 

Off topic, but I noticed a few other curiosities in that video clip:

Should the PFD and ND blank after switching off the engines? Wouldn't Standby Power take over almost immediately? The Upper EICAS seemed ok.

No.  The Captain's PFD and ND displays are normally fed from the Captain's APU Standby Bus which is powered by the APU standby inverter and this in turn is powered by the APU battery through the APU hot battery bus. The Co-pilot's APU Bus is powered by its normal source.   

Shouldn't there be an [RA] flag on the PFD with no main bus power to the Radio Altimeters?

Yes. Left RA with an AC Bus3 failure.  Right RA with an AC Bus2 failure and Center RA with an AC Bus1 failure.

Should there be an [FD] flag on the PFD? I'm not sure how it would behave with the MCP unpowered.

Things would have to be really bad for the MCP to be unpowered because its power source comes from DC Buses 2&3.    In single channel A/P operation any failures of the active mode will be annunciated on the PFGD.

Should the heading cursor be in view on the ND? The MCP is dead, so no computed data.

Source loss or invalid data to the HDG display should show up as dashes.  However, heading information to the NAV display is supplied by the selected IRU.

Shouldn't the Brake Pressure Gauge be showing fully zero (power normally comes from the Ground Service Bus)?

This instrument shows the brake accumulator pressure, so provided some brake pressure is still present it shouldn't read zero. 

[Qavion2 39]

On 12/17/2018 at 8:20 AM, berts said:

Should the heading cursor be in view on the ND? The MCP is dead, so no computed data.

Source loss or invalid data to the HDG display should show up as dashes.  However, heading information to the NAV display is supplied by the selected IRU.

Actually, I was talking about the selected heading cursor here.

 

On 12/17/2018 at 8:20 AM, berts said:

Shouldn't the Brake Pressure Gauge be showing fully zero (power normally comes from the Ground Service Bus)?

This instrument shows the brake accumulator pressure, so provided some brake pressure is still present it shouldn't read zero. 

The pressure sensor needs power. Without power, the needle will go to the zero endstop. Wiring Schematic reference 32-41-03. During Standby Power operation, the Ground Handling Bus is unpowered.

Cheers

JHW

P.S. I don't have the latest version of QOTS II, so perhaps someone can recheck these and submit a ticket?

 

 

Edited December 23, 2018 by Qavion2

[berts 97]

On 12/23/2018 at 10:05 PM, Qavion2 said:

Actually, I was talking about the selected heading cursor here.

What the first video shows is not normal behaviour by any stretch of the imagination and to be fair to PMDG I suspect the symptoms we are seeing probably has more to do with the simulator program 'crashing' rather than any fault in PMDG's modelling of the aircraft's systems.  Without being able to see all of the panel states and EICAS messages clearly, any assumptions either of us make about the validity of what we think we are seeing must therefore be treated with a considerable degree of caution. 

Whilst I agree the MCP looks as if it has died, I don't know for sure.  The IRS's still appear to be operating in NAV mode, so maybe the HDG & Cursor information might still be valid and retained temporarily in the FMC's memory - who knows?!

 

On 12/23/2018 at 10:05 PM, Qavion2 said:

The pressure sensor needs power. Without power, the needle will go to the zero endstop. Wiring Schematic reference 32-41-03. During Standby Power operation, the Ground Handling Bus is unpowered. 

The Ground Handling Bus can only be powered on the ground from the No1 Gnd Pwr receptacle or the No1 APU Generator, but it is impossible to say if the aircraft in this video is still in flight or on the ground! 😂🤣😂

According to the information I have the Parking Brake system is powered from the Main Battery Bus. However, you previously stated the Ground Service Bus powers the brake pressure gauge, so provided the Battery switch is ON and the Standby Power Selector is in AUTO, then the Ground Service Bus should normally be powered automatically in flight and on the ground whenever AC Bus 1 is powered. 

 

[Qavion2 39]

On 12/24/2018 at 9:05 AM, Qavion2 said:

During Standby Power operation, the Ground Handling Bus is unpowered.

Sorry.. I used the expression Ground Handling Bus instead of Ground Service Bus at one point in my response. But, yes, the brake indicator runs off the GSB.

 

On 12/27/2018 at 11:12 AM, berts said:

However, you previously stated the Ground Service Bus powers the brake pressure gauge, so provided the Battery switch is ON and the Standby Power Selector is in AUTO, then the Ground Service Bus should normally be powered automatically in flight and on the ground whenever AC Bus 1 is powered. 

I recall that PMDG's 744 automatically powers the GSB when the aircraft is powered using the GHB (even though manual intervention is required at door Left 2 on the real aircraft)  I doubt this was a factor in the video, however.

[Ephedrin 418]

On 12/15/2018 at 11:25 PM, Jet_Pack2 said:

additional info:
- before starting the flight I entered 0 fuel, 0 passengers, 0 payload from within FSX default fuel menu,

you really must not touch the default FSX payload window when using PMDG addons. not to add and not to remove any fuel.. These airplanes simply don't work this way and all the calculation by the FMC (and likely the fight model)  gets screwed up. 

Quote

inside the aircraft I used the FMS menu option to set 20% fuel

that's absolutely everything that is needed at any point.

Edited December 29, 2018 by Ephedrin
wrong quotation

[berts 97]

34 minutes ago, Qavion2 said:

I recall that PMDG's 744 automatically powers the GSB when the aircraft is powered using the GHB (even though manual intervention is required at door Left 2 on the real aircraft)  I doubt this was a factor in the video, however.

Yes, the Ground Service switch at 2L can be used to power the Ground Service Bus when the aircraft is on the ground with AC Bus 1 unpowered.  Otherwise it would need Superman instead of a Ground Engineer to plug the Ground Power Unit into the aircraft in this video!  

[Qavion2 39]

2 hours ago, berts said:

Otherwise it would need Superman instead of a Ground Engineer to plug the Ground Power Unit into the aircraft in this video!  

.. and it doesn't look like the APU is running.

[faandean 1]

Hey guys, its a very old bug since the early 747-400 release last year. I've been experiencing this issue and it tends to happens when theres a strong wind or gusting.

I did land at Tromso, Norway last month with a gusting of 24kts, using Active Sky as weather generator. And upon a touchdown surely my speed from 140kts magicly goes up to 180kts and easly rotate and go around with idle thrust. Unfortunately i dont have this scenario recorded, however i have one back in March 2017 here:

Back in that video i still using Ezdok and Opus, i upgraded my self to Chaseplane and Active Sky after having those problem and the bug still exist.

 

Edited January 4, 2019 by Olympic260

[Olympic260 415]

5 minutes ago, faandean said:

Hey guys, its a very old bug since the early 747-400 release last year. I've been experiencing this issue and it tends to happens when theres a strong wind or gusting.

I did land at Tromso, Norway last month with a gusting of 24kts, using Active Sky as weather generator. And upon a touchdown surely my speed from 140kts magicly goes up to 180kts and easly rotate and go around with idle thrust. Unfortunately i dont have this scenario recorded, however i have one back in March 2017 here: https://youtu.be/rGNOpy_WxSs

Back in that video i still using Ezdok and Opus, i upgraded my self to Chaseplane and Active Sky after having those problem and the bug still exist.

 

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