05-03-05

Elite Prop Seneca III

A final screenshot showing the Seneca in a single-engine climb. The left engine has failed, the aircraft is climbing out slowly at blue line speed, achieving a "nice" rate of climb of slightly above 300 feet per minute.
 
Notice the lights on the annunciator panel, indicating from left to right:
*) Low oil pressure (because the left engine is failing)
*) Left vacuum low (because the left engine is driving this vacuum pump)
*) Alternator problem (each engine has an alternator to drive)
*) Right overboost (right engine is producing too much power)
 
The last overboost problem is a typical example of the advantages of flying a Seneca V, compared to the Seneca III. When setting the throttle full open, the manifold pressure on a normal aspirated piston engine is the ambient atmosphere pressure (hence somewhere around 29.92 inHg or 1013hPa at sea level, reducing when climbing). The Piper Seneca III/V has turbocharged engines that can boost the manifold pressure to 38 inHg up to altitudes of 10000 feet. Absolute maximum is 42 inHg. Above 42 inHg the engines can be damaged so you have an overboost warning on the Seneca III. This is what you see in this screenshot, the right engine is overboosted, the pilot needs to reduce the throttle to protect the engine. So on the Seneca III, in the high power range and at lower altitudes, the pilot has to be very carefull not to overboost the engine.
 
The Seneca V however is equiped with a wastegate, which controls this pressure automatically. Hence you won't get the overboost situation, unless in extreme conditions (or when the system breaks down). The pilot has to worry less about overboosting the engines when advancing the throttles, the system protects the engine. This is a really nice feature, especially when dealing with engine failures, stalls,...


22:46 Gepost door BraceBrace | Permalink | Commentaren (0) |  Facebook |

Elite Prop Seneca III

Another screenshot, this time at night and at Brussel National Airport (runway 02).
 
Some information on the instruments: the central instrument with the blue and brown section is the artificial horizon, the most important instrument there is. Below it the HSI or Horizontal Situation Indicator. The HSI is a slaved compass with a specific navigation instrument on top.
 
To the left of the artificial horizon is the speed indicator, a very interesting instrument that contains a lot of color information. The "speed envelope" is limited by two red lines, the highest being the "never exceed speed", the lowest the "single engine minimum control speed". The yellow tape indicates speeds to be used in smooth air only, the green tape indicates what you could call the "normal safe" speeds. The lower end of the green bar is the clean stall speed.
 
At the low speed end, the green bar has a white line on top of it (between 115 and 64kts approximately), this indicates the range of speeds where full landing flaps (40°) can be used. The lower end of the white line is the stall speed with landing flaps set to 40°. The small blue line (at 92kts) is the single engine best rate of climb speed, a very important speed when dealing with an engine failure. Whenever we climb on one engine, this is our target speed.
 
The very thick white line below the green line (from +/- 105 to 165kts) is a moveable scale that can be used to calculate True Air Speed (TAS) in flight.
 
To the right of the artificial horizon we have the altimeter, indicating the altitude at which the aircraft is flying. Below the altimeter, you find a vertical speed indicator (showing a descent of approximately 450 feet per minute). Further down is a VOR indicator, a navigation instrument.
 
Below the airspeed indicator is the turn & slip indicator. The small aircraft indicates if the aircraft is turning, the ball if the aircraft is slipping/skidding. Further down is an RMI (radio magnetic indicator), which is basically a slaved compass system with needles pointing to navigation stations.
 
To the right of these flight instruments, you can see a stack of engine instruments. From top to bottom: MAP (manifold pressure), RPM (revolutions per minute), EGT (exhaust gas temperature) and fuel flow. Below these instruments, a series of smaller needles indicating fuel quantity, oil pressure, oil temperature and cylinder head temperature.
 
Further to the right is an annunciator panel, below that the avionics stack with radio, navaids, transponder, autopilot and GPS. And the thing above the annunciator is ... a compass.

22:22 Gepost door BraceBrace | Permalink | Commentaren (0) |  Facebook |

Elite Prop Seneca III

Due to the "bad" weather of the last couple of days, time for some more simulator information. This is a screenshot of the Seneca III add-on of the Elite flight simulator.
 
The Piper Seneca is the type of aircraft we use for our annual multi-engine IFR proficiency check. A small piston twin constructed by the New Piper, Inc company, with room for 1 pilot and 5 passengers. The latest version is the V, used by ie the Sabena Flight Academy and Ben Air Flight Academy. Many schools use the Seneca III (Propeller ie), which is a previous version of the V. There is not much difference between the III and the V, they are almost the same, except that the V has some extra systems making it easier for the pilot to fly it.
 
The screenshot shows the aircraft short final runway 29 at Antwerp-Deurne airport, slight crosswind from the north.


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