How about FF at sea level on takeoff, some aircrafts should show 24GPH but they only show 22GPH
Tell your mechanic to adjust it. If he argues otherwise, get a new mechanic.
Tell your mechanic to adjust it. If he argues otherwise, get a new mechanic.
The max fuel flow of a fuel servo is set by the hard stop on it, not by the cable adjustment. It should be done on an airflow calibration rig.
I am not sure what an airflow calibration rig is or how it is used in fuel flow settings; as far as the Continentals are concerned including these powering the SR22, TCM SID 93-7 rev. G gives you the unmetered pump and metered nozzle fuel psi to achieve at idle rpm and max rpm in order to get necessary fuel flow at takeoff. Either a “Porta-Tool” or two calibrated pressure gauges can be used (diff. pressure gauges for turbo engines).
If the engine doesn’t show the proper fuel flow with static max rpm, TCM’s recommended solution is not beginning the takeoff roll to generate airflow, but rather beginning the taxi back to the shop.
Maybe there is a different fuel servo on the TIO-550.
If that is the case then TCM definitely is unaware!
Remember that the TCM system both on IO and TSIO engines does not have a diaphragm measuring the psid across the venturi like the Bendix servo, it meters exclusively based on fuel pressure, and fuel press measurements are taken off specific fuel pump ports, where adjustments are made as well.
In theory it should be done every 100 hours, and it is not always easy to get right as the full throttle psi adjustment influences the idle adjustment and viceversa.
Directly from the horse’s mouth. There can be no “different servo on the TIO-550” as TCM engines don’t have a servo to begin with.
If that is the case then TCM definitely is unaware!
Clearly that must be the case, T28. That is a fuel servo. TCM just don’t know it; they just screw this magical thingy they get on Ebay to the bottom of the engine and hey it just magically does he right thing 
But perhaps the OP would appreciate getting back on the SR22 operating costs topic. If somebody found a way to prevent turbo engines cracking cylinders, by adjusting this “device”, that would be most interesting to many. I very much doubt it because to get the CHT down even more than is the case under the normal adjustment, the engine would be so rich it won’t be making much power.
Peter wrote:
If somebody found a way to prevent turbo engines cracking cylinders, by adjusting this “device”, that would be most interesting to many.
That would be interesting to figure out
Peter wrote:
I very much doubt it because to get the CHT down even more than is the case under the normal adjustment, the engine would be so rich it won’t be making much power.
But if too rich to generate power it will be too rich to generate heat, so problem solved
In my experience, CHTs in climb are very sensitive to a simple drop of RPM from 2700rpm to 2600rpm and increasing ASI by 10kts than 1GPH from the mixture but for a full power takeoff that 1GPH may make some difference
Of course some pilots still fly steep VX climbs on full power with the yaw ball sitting in the right corner even when it’s 20G30 headwinds and 5km runway
Peter the Cirrus nose gear (like most other aircraft) can be damaged by a heavy/nose first landing but it is a very rare occurrence, the vast majority of the fleet are still running their original part. If your ‘friend’ is replacing this item every two years then it’s not the design or manufacturing that needs looking at.
The guy in question – who would not give me permission to post the pic below, due to warranty politics, enabling me to take a load of flak – has got out of flying some time ago.
Apparently this was quite a common problem in the UK. A few k £ each time.
From here
I spent the weekend looking at my annual invoice, the fin repair invoice, and the estimate for the fuel pump that decided to break just as I was planning to pick up the plane from maintenance.
I also had time to wonder (and feel pity for myself) why I got so unlucky over the last two months and £25k poorer.
:)
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