Get this 2 Master warning

[ga 1]

see the picture I get this Master warning regarding "Air cooler" (right warning on pictures) when I desent think about just below FL100,See also the left light with "oil pressure" what is this about?

[Cristi_Neagu 10]

For the first problem, your pressurization panel is not set properly, unless your cruising altitude was FL100. Do the tutorial.Sorry about that. I looked at the thumbnail and i thought it said 10000. You get "off scheduled descent" if you've started your descent before reaching the altitude you put in the pressurization panel.

[xxJohnxx 21]

The left light is there because you have started the APU some seconds ago. When the APU is running, the light will turn off.Have you done the tutorial flight? Because the right one has to do something with the pressuration system. You don't have set the correct crouise level and you also forget the landing altitude.

[xxJohnxx 21]

The second problem looks like you need to turn the APU off !

Look at the EGT. The APU isn't even running.

[ga 1]

Ok Gents thx, this flight was just a saved mission I used for testing out landing ILS and probely did not set it totaly correct up ;)But thx gott both Info I needed, salute ;)

[davierosoft 13]

OFF sched descend is already answered, about APU if the light will stay on minutes after selecting START with no EGT increase in the gauge, your APU is faulty.

[Chris_FL 0]

The APU switch is "On" but the EGT shows 0. I believe I read the APU cannot be started above a certain altitude, perhaps thats what happened here?

[RYR738 8]

The APU switch is "On" but the EGT shows 0. I believe I read the APU cannot be started above a certain altitude, perhaps thats what happened here?

The APU on a 737 NG can be started and operated up to the plane's max cruise altitude ! 41,000 feet.

OFF sched descend is already answered, about APU if the light will stay on minutes after selecting START with no EGT increase in the gauge, your APU is faulty.

On the NGX only if you have failures set !! On a real plane you would also have the FAULT light on all the time.

[VIPERGTSR01 17]

The APU on a 737 NG can be started and operated up to the plane's max cruise altitude ! 41,000 feet. .

It can be operated to 41000ft on electric only, 17000ft on bleed only, 10000ft on both. However it can't be started above roughly 25000ft. Try starting it next time you're in cruise.

[nharwood 0]

I thought the 25,000 start recommendation was for the 737 classic, with no (start) limits on the Allied Signal unit used in the NG. Regards, Nathan Harwood

[davidz 26]

As a matter of interest, the OFF SCHEDULE LIGHT will only illuminateif you abort a climp to the set altitude.Would normallt be seen if a flight had a problem and had to land again.

Yes - Off Schedule Descent is commands the pressurisation system to descend to the departure aerodrome elevation, rather than the "LAND ALT" setting.

[VIPERGTSR01 17]

I thought the 25,000 start recommendation was for the 737 classic, with no (start) limits on the Allied Signal unit used in the NG. Regards, Nathan Harwood

It's in the NG manuals, plus it's like that in the NGX , I tested it quite thoroughly.

[nharwood 0]

I don't mean to be argumentative, but I thought that ETOPS-compliant APUs must be flight-startable at altitudes up to the aircraft service ceiling. If the APU or its electrical generator is not available, the aircraft cannot be released for ETOPS flight. A cold soak APU start, at altitude, is also required every 30 days for ETOPS compliance. Many airlines track this and send an ACARS message to in-flight crew when this time comes to perform and log this. FCOM 7.30.1 states that "The APU starts and operates up to the airplane maximum certified altitude." However, the QRH section 6.5 states "Note:APU start attempts are not recommended above 25,000 feet." when both engine driven generators are inop. To start the APU above FL250 might require more battery capacity (due to multiple start attempts) than recommended. I guess I'll be trying this more during tomorrows flight! Regards, Nathan Harwood

[VIPERGTSR01 17]

I know they have to be operational at ceiling for ETOPS but haven't heard they have to able to start at ceiling, especially considering the main engines wont (in most cases) start at or around ceiling. I know of atleast a couple airlines start the APU on ground for ETOPS due to starting issue mid air, it's cheaper to just have it running from the gate than descend for APU start then re-ascend to cruise. What I know for sure is the NGX's APU wont start too far above 25000ft

[davierosoft 13]

The APU generator can supply 90 KVA electrical power up to 32,000 feet (9,754 meters) and 66 KVA to 41,000 feet (12,500 meters). Electrical and pneumatic power is available at the same time up to 10,000 feet (3,048 meters). Pneumatic power alone is available up to 17,000 feet (5,183 meters). The APU can be started at 41,000 feet or below.

This is on the paper, if it really starts at the first attempt above 25000ft is another thing.Maybe it is considered that APU will be started in a condition of a single generator lost, so, the starting is through the AC XFER bus 1, in this condition you have a lot of start attempts, paying attention to the limits for starter consecutive engagement, EGT and other factors)

[Spin737 102]

I know they have to be operational at ceiling for ETOPS but haven't heard they have to able to start at ceiling, especially considering the main engines wont (in most cases) start at or around ceiling. I know of atleast a couple airlines start the APU on ground for ETOPS due to starting issue mid air, it's cheaper to just have it running from the gate than descend for APU start then re-ascend to cruise. What I know for sure is the NGX's APU wont start too far above 25000ft

On the 737 in the US and Canada are West Coast-Hawaii routes. Like you said, it's just cheaper and easier to leave them running up until the EXP. However, not all flights enter ETOPS right away, eg. Seoul-Urumqi. In that case, the APU would be started 45 minutes prior to EEP Also, there is the APU On Demand program, which will allow airlines to use the APU on demand if they pass certification. That certification requires the cold soaked APUs to start at cruise above FL290. Did you try multiple starts?

[VIPERGTSR01 17]

Did you try multiple starts?

Sure did and I broke it lol