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View Full Version : 737-800 Pitch bar show 10 degrees nose down


ANAJASJAL008
5th Oct 2018, 01:49
Hello,

The pitch bar is at 10 degrees down because I am rolling at less than 60 KIAS.
But why does the pitch bar show nose down?
I think that it is easier to understand if the pitch bar show nose up from the beginning.

Thank you for your answers.

A37575
5th Oct 2018, 16:27
But why does the pitch bar show nose down?
Encourages the FD addicted pilot to keep light forward pressure on the control column as per FCTM advice... https://www.pprune.org/images/smilies/thumbs.gif

ANAJASJAL008
6th Oct 2018, 14:57
Thank you very much A37575.

Is this behavior the same for 737-400 and 737-200 too?
Nobody knows?

Banana Joe
7th Oct 2018, 12:10
Yes on the Classic. Can't speak for the -200.

kenparry
7th Oct 2018, 15:42
Is this behavior the same for 737-400 and 737-200 too?

Not on -200. Very different instruments, all analogue, the attitude display driven by a vertical gyro.

I-2021
7th Oct 2018, 16:15
Thank you very much A37575.

Is this behavior the same for 737-400 and 737-200 too?
Nobody knows?

As far as I can remember (that was a long time ago), on the -200 You needed to manually select the FD pitch attitude that You wanted to maintain and therefore it was rarely used as it induced more workload than anything. The -230 advanced on the other hand had an AFDS similar to the classics and I think it used the same principle but I should definitely check in the FCOMs that I do not have anywhere handy at this time. Maybe somebody can contribute a little more to this nostalgic moment ;-)

Matey
8th Oct 2018, 00:06
On the -200s that I flew (basic and advanced aircraft), the pitch bar was set manually to wherever you wanted it except when on the ILS when it gave commands to follow the glideslope. The only autopilot pitch mode available was CWS from both Captain and First Officers sides except when following a glideslope. Heading Select only available from the Captains HSI so the First Officer flew in CWS and asked the Captain to update the heading bug. The standard call was “match me heading and modes.” Happy days,great aircraft to fly. The Classic flight director gives the same commands as the NG for take off

Vessbot
8th Oct 2018, 00:40
So... no altitude hold?

ANAJASJAL008
8th Oct 2018, 12:41
Hello Gents,

Thank you for the detailed explanation. 737 family have a long history, so these change a lot.

Warm regards,

I-2021
8th Oct 2018, 18:19
On the -200s that I flew (basic and advanced aircraft), the pitch bar was set manually to wherever you wanted it except when on the ILS when it gave commands to follow the glideslope. The only autopilot pitch mode available was CWS from both Captain and First Officers sides except when following a glideslope. Heading Select only available from the Captains HSI so the First Officer flew in CWS and asked the Captain to update the heading bug. The standard call was “match me heading and modes.” Happy days,great aircraft to fly. The Classic flight director gives the same commands as the NG for take off

Thanks for the revival Matey, now I have a few distant memories coming back to my mind. We used the same procedures, I also remember we had the ALT HOLD and ALT ACQ function on the MCP selector, basically You need to select Your cleared altitude in a small panel in front of the thrust levers (or somewhere in that area, just above the Wx Radar box I think) and then pitch to maintain 1000 ft/min for the last 1000 ft below the cleared level and the AP would gently level off at that altitude. You would then need to select ALT HOLD on the MCP. That is what I vaguely remember from these days, it was a lot of fun and those JTD would burn tons and tons of gas !

Matey
8th Oct 2018, 23:06
Thread creep I know. Alt Hold yes, but no posh Alt Acq in Britannia aircraft! We did, in later years, have an Omega navigation system which used VLF radio signals originally designed for submarine navigation. You entered the Lat/Long of a waypoint and it basically told you whether you were left or right of a desired track. Went “walkabout” quite a lot though. A bit of a step up from the dead reckoning we had to use between Santiago VOR and Porto Santo NDB when radio signal ran out on the way to the Canaries. Unlike today, often the only time you saw other aircraft on your route was overhead radio aids before meandering off again.

I-2021
8th Oct 2018, 23:12
Alt Hold yes, but no posh Alt Acq in Britannia aircraft! We did, in later years, have an Omega navigation system which used VLF radio signals originally designed for submarine navigation. You entered the Lat/Long of a waypoint and it basically told you whether you were left or right of a desired track. Went “walkabout” quite a lot though.

Wow the Omega that was some serious stuff eheh. We were lucky enough to have a Marconi GPS that You could even slave to the CM1 HSI and fly RNAV5 airspace... even more posh !
Sorry for the off topic folks !

Matey
8th Oct 2018, 23:48
Britannia originally bought the -200 to be able to fly from Luton to Palma (around 2hrs 20) with a full load of 130 passengers and normal reserves. By the time they were phased out, with all the engine and weight upgrades we were regularly flying 5 hour sectors. Great performance too as we could get back to the UK from most performance limited airfields without tech stopping enroute, unlike competitors flying other types. JT8D fuel flow if I recall rightly was around 2400kg per hour to carry those 130 passengers at Mach .72.. The NG has a similar fuel flow but carries 189 pax at typically Mach .78. The MAX-8 similar fuel flow again, but over 200 passengers. OK...back to the NG flight director!