Hi All:I have a small problem with pressurizing the FSD Aerostar 700.If anyone uses this aircraft, would like a layman

Is it something as simple as turning the air source on? Unfortunately, there have been several accidents over the years attributable to forgetting to turn on the bleed air or other air source. Pressurization is a fairly simple concept. You blow air in and regulate how much excapes. Its the control and regulation that gets more complex.

Tks. Mike for your reply.It has to be something simple, I do have two control knobs which say Alt Air. Left and Right.It is possible that I have these two Air control closed, unsure if they should be pulled out or left in when climbing.I could not find any instructions on what position they should be to be open.I have no problem with the bleed air open or door inflate. Examble set cabin alt to 4000 and Aircraft Alt to 15000. When climbing the Aircraft Alt needle moves to the current altitude of the aircraft but the Cabin Alt. needle remains at 0.When I reach the Altitude of 12,000 is when the Oxygen requirement light comes on and the Cabin Alt remains at 0.Hope this explains the problem.Kenny G.

HI Kenny. Been a long time since i flew this bird (more that a year at least) I gave up on FSD products (I had 3) after several support experiences similiar to your's. I was puzzled for a while by the 700's pressure system but eventually worked it out. If an answer doesn't come before then, I will take a look over the weenend when I am at the flight sim machine. However a first issue is to make sure you do not have the dump switch on (as I think it is called). As I recall, you test this during the run up. I may be confusing with the Aeroworx Beech 200 (a fabulous bird similar in type with a patient support staff). As I recall, it was definitely important to follow the checklist. Cheers

Kenny,Its been many years since I flew this category of airplane but, if memory serves me, the Alt Air knobs relate to the pitot system in case it gets plugged. Sounds to me like the outflow valves are staying open. I never flew an Aerostar so must be something else. Good luck.

Hi All:)Thanks for your assistance, I have Bleed air on both right and left, door inflate dump normal.Unsure on the Alt air the knobs do not indicate whether open or close.I will try them in different positions.I have read the prodeedures like I said numerous times, but still can't get that #### Oxygen Required light to stay off after reaching 12,000.The Cabin Altitude needle does not move only the aircraft Altitude needle.Tks again Kenny G.

If the cabin altitude stays at zero, perhaps the pressurizatiion is OK but a sensor is telling you that your emergency O2 is low meaning insufficient Oxygen for a loss of pressurization emergency descent.

Hi Kenny, You need to set two values.1. Desired cabin altitude2. desired rate of changeThe pressurisation gauge found in most light/medium aircraft has 3 pointers.1. Cabin altitude2. cabin/ambient differential pressure3. CABIN rate of climb/desentAircraft altitude is not indicated on this gauge under normal operation.Roger

Hi RogerYou are correct it is just my interpretation of the guages.Example I roll the Aircraft cabin altitude to 4,000 and the bottom scale indicates 14,000 and 15,000.When climbing the Differention pressure needle climbs as the aircraft passes through the various altitudes during its climb, but the cabin Altitude needle remains at 0 altitude and does not move.If I could get the cabin altitude to climb as per the differential the problem would be solved.I am still reading the POH for the 100th time should find the problem some year LOL.Take care.Kenny G.

Some basic pressurization systems will maintain your selected cabin altitude untill you reach max differential then start to climb.Try leaving the cabin set at sea level or close and climb to service ceiling and see if cabin starts to climb when max differential is reached.

>HI Kenny. Been a long time since i flew this bird (more that>a year at least) I gave up on FSD products (I had 3) after>several support experiences similiar to your's. I was puzzled>for a while by the 700's pressure system but eventually worked>it out. If an answer doesn't come before then, I will take a>look over the weenend when I am at the flight sim machine. >However a first issue is to make sure you do not have the dump>switch on (as I think it is called). As I recall, you test>this during the run up. I may be confusing with the Aeroworx>Beech 200 (a fabulous bird similar in type with a patient>support staff). As I recall, it was definitely important to>follow the checklist. CheersStill havn't come up with the answer yet, if you do get a chance to get your Aerostar up and running this week-end could you get back to me.Tks. again.Kenny G.

Kenny,>Example I roll the Aircraft cabin altitude to 4,000 and the>bottom scale indicates 14,000 and 15,000.OK mate the 4,000 ft is the selected cabin altitude.The 14,000 - 15,000 ft at the bottom indicates the aircraft FLIGHT altitude at which maximum cabin/ambient differential will be reached -(with 4000 ft in the cabin).What you still haven't done is selected the rate at which you want the cabin to go from the airport altitude to 4000 ft. I suspect that it is presently set at 0 ft/min. Thus when you fly the cabin altitude is going nowhere fast. :-)BTW this cannot happen in real life - the minimum rate of change setting is 50 ft/min. All the above is only a theory as I don't have the Aircraft- or even use FS 2004.look closely at the knob that sets cabin altitude. Is there a dual concentric knob that enables you to set Rate of change??If not have a good close look at the pressurisation controller for any othe knob that will do this.Look for a knob that can be set/aligned to a little "filled in triangle".That setting represents 300 ft/min. Once flying you can readjust the cain rate of change setting using the cabin rate of change pointer as an indicator. Just one other observation. The cabin altitude is typically set at 300 ft/min so the rate of movement of the cabin altitude pointer is quite slow. 3 minutes per 1000 ft. To get from sea level to 4000 will take approx 13.3 minutes!!edit: I should also mention that the aircraft flight altitude MUST be above 4000 ft or the cabin cannot go to 4000 ft. IE in a pressurised aircraft the cabin ALTITUDE cannot be higher than the aicraft flight altitude. ( aircraft are not Submarines: they are not designed for negative differential pressures)>I am still reading the POH for the 100th time should find the>problem some year LOL.Yep, when all else fails. See what the manual has to say about setting up pressurisation.Cheers,Roger

Tks. Roger will take your advise and try again LOL:)Kenny G.

>Kenny,>>>Example I roll the Aircraft cabin altitude to 4,000 and the>>bottom scale indicates 14,000 and 15,000.>>OK mate the 4,000 ft is the selected cabin altitude.>The 14,000 - 15,000 ft at the bottom indicates the aircraft>FLIGHT altitude at which maximum cabin/ambient differential>will be reached ->(with 4000 ft in the cabin).>>What you still haven't done is selected the rate at which you>want the cabin to go from the airport altitude to 4000 ft. I>suspect that it is presently set at 0 ft/min. Thus when you>fly the cabin altitude is going nowhere fast. :-)>BTW this cannot happen in real life - the minimum rate of>change setting is 50 ft/min.> All the above is only a theory as I don't have the Aircraft->or even use FS 2004.>>look closely at the knob that sets cabin altitude. Is there a>dual concentric knob that enables you to set Rate of change??>If not have a good close look at the pressurisation controller>for any othe knob that will do this.>Look for a knob that can be set/aligned to a little "filled in>triangle".>That setting represents 300 ft/min. Once flying you can>readjust the cain rate of change setting using the cabin rate>of change pointer as an indicator. >>Just one other observation. The cabin altitude is typically>set at 300 ft/min so the rate of movement of the cabin>altitude pointer is quite slow. 3 minutes per 1000 ft. To>get from sea level to 4000 will take approx 13.3 minutes!!>>edit: I should also mention that the aircraft flight altitude>MUST be above 4000 ft or the cabin cannot go to 4000 ft. IE in>a pressurised aircraft the cabin ALTITUDE cannot be higher>than the aicraft flight altitude. ( aircraft are not>Submarines: they are not designed for negative differential>pressures)>>>I am still reading the POH for the 100th time should find>the>>problem some year LOL.>>Yep, when all else fails. See what the manual has to say about>setting up pressurisation.>>>Cheers,>>Roger>Hi RogerI tried all of the above and still can't get the cabin rate of change pointer to move from 0 Altitude even when the differential pointer is moving with the altitude of the aircraft.The rate of change knob when the aircraft is loaded defaults to 300 FPM. Tks. for your advise will keep trying.ByeKenny G.