Plane crash in Iran
 

Passenger plane crashes in Iran mountains - BBC News

Not much detail yet other than:

* was routing Tehran - Yasruj
* around 60 aboard
* came down in a mountainous area in Central Iran

Iranian aircraft with 60 people on board crashed near the city of Semirom in the Isfahan Province of Iran, according to Tasnim news agency citing Iran's emergency centre. The aircraft went off radar midflight from Tehran to Yasuj.

According to TV2 Denmark quoting Tasnim and Fars it's an ATR 72 of Aseman Airlines

According to the BBC bad weather is hampering rescue efforts

https://www.mirror.co.uk/news/world-...eople-12045621

"Witnesses told local media that it appeared the aircraft was trying to make an emergency landing on a pasture before it crashed in the Dena mountain range."

ATR72-500 according to the latest on this on the BBC,

Passenger plane crashes in Iran mountains - BBC News

Aseman Airlines plane, en route from Tehran to the south-western city of Yasuj, came down in the Zagros mountains.The Red Crescent deployed search and rescue teams to the site near the city of Semirom in Isfahan province. Flight EP 3704 left Tehran at 08:00 local time (04:30 GMT) and disappeared from radar about an hour later. The aircraft crashed on Dena Mountain, 22km (14 miles) from Yasuj, news channel Irinn reported. The plane was a French-made twin-engine turboprop ATR 72-500. On board 60 passengers, 2 security guards, 2 flight attendants and the pilot and co-pilot.
No survivors.
+
The aircraft involved is a 24 year old ATR 72. Registration EP-ATS. MSN 391.According to FR24 logs flight took off at 04:33 UTC. Last signal was received at 05:55 UTC when flight was at 16,975 feet and descending. FR24 state they can only use MLAT for tracking as the six types of the airline carry old type xpdrs.

If it’s 24 years old it can’t be a -500 (properly -212A) AFAIK, which came out I believe in 1997. Anyway, a sad day regardless of the minor details.

Mountains, snow, bad weather, quite "interesting" circling NDB approach and teardrop ... not a combination you want that often.

Jeppesen has only two charts. Appears a VOR/DME was recently installed. Interesting there is no departure procedure.

Per Av Herald the crash site is about 16 miles west, northwest of the airport.

The Associated Press is reporting that until a few months ago the aircraft had been out of service for seven years.

Reportedly WFU due to shortage of spares.

Some bits from Twitter
 

Video supposedly showing a couple of seconds of final approach into Yasuj on a ATR a few months ago:


Iranian Aerospace Forum on Twitter:

One PAX reportedly a no show.

Aircraft overhauled after a few years in storage due to lack of spares, put back in service in November 2017:


This supposedly shows the weather conditions in the area:

Weird, there is such a long valley lining up with that runway in Yasuj, hard to imagine the need to be so low WRT those mountains in the northwest in that clip.

We don't know yet of course but I would very much doubt that aircraft serviceability had any role in this. More likely a scenario relating to weather and procedures.

A really lousy NDB approach. Wonder whether the Iranian aviation authority was/is working on a VOR approach? They spent the funds to install that VOR/DME recently.

from the BBC

Found? No, not confirmed yet.

Can you name the source? I'm not meaning to sound doubtful and all, but that is a lot of time for bird to be on the ground if it wasn't properly looked after. Thanks.

Re: Source

The Guardian reports, citing Iranian media:

Also, see the tweet by Iranian Aerospace Talk Forum I cited above. This could be sourced from the allegedly deleted instagram post.

The missed approach from MDA demands accurately tracking an NDB back bearing. Not every ADF installation does back bearings as well as front bearings.

How many crews today can do a good wind correction on an NDB bearing?

Was there any calibration flown on the approach?

Even more exciting would be flying a missed from as much as 4000' below the MDA. Was calibration for the missed flown from just above the runway?

The old salt Russians. Dual ADFs on RMIs.

Only Iran knows that.

That might not be part of Iranian flight inspection specs. Or, many other countries for that matter.

I believe the recent installation of the VOR/DME is evidence that Iran was on the path to improvement at this difficult airport.

I agree with you.

The economic sanctions placed on Iran years ago caused quite a few aircraft to be sidelined.

TEHRAN, Iran (AP) - Iranian search-and-rescue teams on Tuesday offered the first images of the site of an airplane crash in southern Iran that killed 65 people, with officials hoping to reach the aircraft's "black boxes" to learn exactly what downed the flight.

State television aired footage showing the plane crash site against the side of a snow-covered mountain near Yasuj, some 780 kilometers (485 miles) south of Tehran, Iran's capital from which the Aseman Airlines flight took off on Sunday.

A helicopter pilot interviewed by state television said the crash site appeared to be only 30 meters (100 feet) from a peak on Mount Dena in the Zagros Mountain range.

"Some large parts of the plane, which were labeled with the Aseman company logo, were seen," said the pilot, identified by state TV only as Capt. Soheili.

From now on drone deployment appears to have become a standard tool in both SAR and investigative efforts. Similar use in the Antonov case. And especially helpful in difficult conditions ... Like the high snow in these two 2018 cases. In this case the helicopters could not land and people on foot are the only option. Drones make a search far more efficient and effective which is a great help for those in SAR and contributes to their safety.

What size of drone?
Are we talking 'pilotless aircraft'? - or a portable toylike device?


Edited to add:-

NDBs?
 

They are Non Directional Beacons, surely?

Blockage by terrain could limit the use of an NDB. Flight inspection has to verify signal strength for both the approach and missed approach. A weak signal can cause a false bearing.

It will be interesting to learn whether the flight flew the procedure correctly to well below MDA, then did a missed approach.

It's hard not to feel for this crew. Who knows if they pushed limits but the captain was a veteran and presumably familiar with both airport and the limitations of the approach; as sad end to what was probably a distinguished career.


Not the type of approach facility I would want to deal with in those conditions; especially when they could have had a VOR DME approach there. Was there radar cover in the area or where they expected to let down using own nav? That could explain the end result if the aircraft only had basic kit.

An ADF That doesn't allow tracking outbound from the NDB?
How the heck would you do an NDB approach?

I think the poor chap is getting confused with a Back Course ILS. He obviously has never flown an NDB let down in his life (unlike me).

Europian Datum 1950 is using in Iran. The height difference from WGS-84 is 30.24 meters.
Therefore, I think it started to decline about 1 km earlier. The distance along the axis of the runway differs by approximately 60 meters (2 arc seconds).
Sorry, the distance along the axis of the runway differs by approximately 30 meters ( abt 1 arc seconds).

On that approach chart 16-1 (dated 20 Oct 17) the minimum altitude during the teardrop turn is given as 12,500 for category A and B aircraft, but 11,400 for the faster C and D categories. I would expect that to be the other way around, i.e. the higher altitude for the faster airplanes with their wider turning radius, as well as their outbound course that is aimed closer to the mountain range in the east.

That occurred to me, too. It would be interesting to see state source; i.e., the official Iranian chart in their AIP. I doubt that is available on-line, though.

Jeppesen is careful, but not perfect.

In any case, the accident did not occur in the area of the base leg.

Actually, the Iran AIP is online, but I couldn’t access the charts on an iPad, requires desktop.

They are Non Directional Beacons, surely?

not the onboard equipment

Everyone is discussing the interesting approach, but it is not clear to me that the aircraft even reached the Yasouj NDB to commence the approach.

Those are some serious Mountains north of Yasouj, and tall mountains, strong winds can create extreme problems in maintaining altitude.

So far, information on the route of the flight has been pretty sketchy. :confused:

ironbutt57:

Exactly so; the NDB is the bit on the ground and the ADF is the bit in the aircraft.