Successful business people (rather like airline managers) always have an eye on their costs. What's the point in spending big bucks when you can get the same service for less?... That's the mentality.

OTOH... They are paying for a door-to-door service because it is convenient to them and they can afford it. That will usually mean that they are not interested in how bad the weather is, or how many hours the crew has flown today, or how few hours TT the pilot has, or maybe if he is even licensed for this type of operation. They have paid a lot of money for this convenience and they want to fly without being bothered about the details.

See this chart for details of the airspace situation. Egelsbach 08 approach is under the departure path of EDDF runway 18.
Lack of flexibility in airspace design... Departing aircraft from FRA are well above any approach path to Egelbach, both could actually use that airspace at different altitude, but this is not forseen in the ICAO standards.

Epic crash EDFE
 

This 'kit' plane was something of a pet project.
Just like S7 as a company is almost an all-family venture, this a/c was sort of labour of love. The pilot was an experienced instructor for their company.
They do have a Gulfstream and dedicated pilots for it. They could easily afford a В737 BBJ if they wanted to.

@ Bsieker:

You are right, my last flight into Egelsbach has been a few Yrs. ago. but that doesnt change anything, ist still a tight Airspace - And a tight Approach to Rwy 08 overflying the Hightension Cables and performing a descending turn onto very short final with Something like Vref+10. And there is no other Appr. possible in that direction.

If traffic Permitted, flying a Turboprop we rather preferred to accept up to 10kt Tailwind and head for the Highperformance Appr. into Rwy (27) .

Company decided to fly to EDDF for Safety reasons, later on.

According to their website the FR24 position data was obtained by MultiLateration (MLAT) and I suspect the groundspeed was likewise calculated from that. I guess that the varying groundspeed will be an artifact of the inaccurate position data.

Perhaps someone with an account can look to see if raw airspeed is available since that is not part of the free offering.

http://www.multilateration.com/surve...ateration.html

I don't recall seeing airspeed on any of the standard FR24 outputs available to subscribers.

Very few aircraft send ADS-B airspeed, so it's only available if the aircraft has Mode S EHS and is being interrogated by a suitably-equipped radar. Even then, it's a bit tricky to decode, though you can usually extract IAS and TAS with a bit of luck.

FR24 data for this flight ends approx. 32 km from destination airport.... Not of much use unfortunately.

If the prop was not turning it would be in the feathered position, obviously not the case in the photo. From the flight manual of an aircraft with the same engine.

A normal PT6 which is shut down without first feathering the prop, will feather itself as oil pressure bleeds off, though it is not immediate (I tried it in a Twin Otter once). It's an avoid though, as from idle, the prop spins for some time until the blades have feathered themselves enough to really slow down quickly. During that time, the gearbox is not being supplied pressure oil I was told.

Though I doubt it on this aircraft, some PT6 propellers have blade latches to hold the blades in flat pitch after shutdown - generally for floatplane operation.

https://www.flugzeugforum.de/attachm...8-png.1278874/

This is the route it took according to the eyewitness mentioned above.

I've always tried to remember that props that lose oil pressure:
- go to feather (coarse pitch) on a multi-engine installation
- go to fine pitch on a single-engine installation.

Does that still apply to turbo-prop installations like a PT6?

It seems to me the reason it would go to fine pitch on a single-engine aircraft is to facilitate a (windmilling) restart. But that does not apply at all to free-turbine turboprops.

The TBM (also single-engine PT6A) manual says that in case of engine failure, the propeller will feather automatically. Counterweights drive pitch to high (coarse), oil pressure moves it towards low (fine) pitch.

Bernd

Until now I had not heard of this type of aircraft. So I looked it up and thought of the old proverb, if it looks good it flies good. This one did not fit the proverb. Looks just like an airfix job that we used to glue together out of the box and hang it from the ceiling. Looks a cow to fly and if it gets to 325kts and lands at 90 then best to get an old time F104 G driver dust the moth balls off him and get him to drive the thing. Cheaper to pay for blown tyres every trip and if that`s too much get a chopper for the short hops.

Thank you for confirming that Bernd, a useful thing to know. There are of course two situations: in case of an engine failure the fine pitch setting could assist a windmill start, but in case of a prop (governor) failure, the fine pitch setting will allow a go-around, at the expense of cruise performance. I was wondering if the second situation would still be valid on a SET.

Another thing I was thinking about is whether, for a free-turbine engine, the prop will keep spinning when one side hits the ground at a low forward speed? As there is no mechanical connection between the power turbine and the gas generator, at a low power setting such as during approach, could you have a situation where the prop is stopped by ground impact and therefore the other blades will not bend?

Yes.

If the prop were unpowered in flat pitch in flight, it would create an unexpected amount of drag, and probably surprise the pilot as to the reduced glide characteristics. That airplane looks like gliding characteristics were not foremost in it's design consideration. That said, PT6 engines are very reliable.

No it wont. The engine is a free turbine, so rotation of the N2 (prop) does nothing in getting the N1 to rotate. N1 has to be a minimum of 12% prior to introduction of fuel for a start.Power available would be minimal. From a flight manual.

PROPELLER GOVERNOR - Under normal conditions, the governor acts as a constant speed unit, maintaining the propeller speed selected by the pilot by varying the propeller blade pitch to match the load to the engine torque. The propeller governor also has a power turbine governor section built into the unit. Its function is to protect the engine against a possible power turbine overspeed in the event of a propeller governor failure. If such an overspeed should occur, a governing orifice in the propeller governor is opened by flyweight action to bleed off compressor discharge pressure through the governor and computing section of the fuel control unit. When this occurs, compressor discharge pressure, acting on the fuel control unit governor bellows, decreases and moves the metering valve in a closing direction, thus reducing fuel flow to the flow divider.

PROPELLER OVERSPEED GOVERNOR - The governor acts as a safeguard against propeller overspeed should the primary propeller governor fail. The propeller overspeed governor regulates the flow of oil to the propeller pitch-change mechanism by means of a flyweight and speeder spring arrangement similar to the primary propeller governor. Because it has no mechanical controls, the overspeed governor is equipped with a test solenoid that resets the governor below its normal overspeed setting for ground test. The OVERSPEED GOVERNOR PUSH TO TEST Switch is located on the left side of the instrument panel.

PROPELLER - The propeller is constant-speed, full-feathering, reversible, single-acting, governor-regulated propeller. A setting introduced into the governor with the PROP RPM lever establishes the propeller speed. The propeller utilizes oil pressure which opposes the force of springs and counter-weights to obtain correct pitch for the engine load. Oil pressure from the propeller governor drives the blades toward low pitch (increases RPM) while the springs and counterweights drive the blades toward high pitch (decreasing RPM). The source of oil pressure for propeller operation is furnished by the engine oil system, boosted in pressure by the governor gear pump, and supplied to the propeller hub through the propeller flange.

Yes. If you had not cut my following sentence, you would see that that is exactly what I said. And so I went on to say that that is, from manuals I have seen, precisely what PT6A installations do not do.

What I actually wrote was:
So I wonder why you felt a need to leave out my second sentence just to repeat the exact same thing I already said.

:confused:


Bernd

Bernd, sorry, I fully recognised your latter sentence, and only made the post as folk may not realise the engine under discussion is a free turbine (PT-6) and to give some info on its operation. :ok: