Aviastar Twin Otter Missing in Indonesia

[Ex RN ATC]

Indonesia's Aviastar passenger plane carrying 10 people is missing | Daily Mail Online (http://www.dailymail.co.uk/news/article-3257440/Passenger-plane-carrying-10-people-missing-Indonesia.html)

[akaSylvia]

Because I hate seeing the Mail as a reference:


ASN Aircraft accident de Havilland Canada DHC-6 Twin Otter PK-BRM between Masamba and Makassar (http://aviation-safety.net/database/record.php?id=20151002-1)

7 passengers, 3 crew

A DHC-6 Twin Otter operated by Aviastar Mandiri is reported missing on a domestic flight in Sulawesi Island, Indonesia.

The flight departed Masamba at 06:25 UTC (14:25 LT) and was expected to arrive at Makassar at 07:39 UTC (15:39 LT). Last radio contact was at 06:36 UTC.

[India Four Two]

There is some fairly rugged and remote terrain on the flight route, including an 11,000' volcano, Bulu Rantemario.

[aterpster]

India Four Two:

There is some fairly rugged and remote terrain on the flight route, including an 11,000' volcano, Bulu Rantemario.

And, I presume, capricious weather conditions of a tropical nature.

[The Ancient Geek]

The Twotter is a tough old bird so a forced landing should be survivable.
OTOH straying into cumulogranitus at 100+ knots is invariably fatal.

We can only hope until the search finds them which can take a while in that kind of territory.

[peekay4]

According to the (Indonesian Meteorology Agency), at the time of the aircraft's disappearance the weather along the planned route was very good with mostly clear skies, light winds and visibility > 10km.

However, today bad weather in the area is preventing SAR teams from reaching a probable crash site, according to local media.

Apparently the location of the probable crash site was determined in part from detection of a mobile phone signal. Aviastar confirmed that the mobile phone belongs to one of the crew members.

This accident hits close to home for investigators. All of the passengers are reportedly employees of the Indonesia's Department of Transportation (Kemenhub) and their families. Six are employees & family members from the departure airport (Masamba) and one is the Chief of the nearby Seko airport.

All of Aviastar's Twin Otters are now grounded pending further investigation.

[unworry]

No details, just this ...

"SEARCHERS have detected a signal from the mobile phone belonging to the pilot of a small plane missing in eastern Indonesia...
Phone signal detected from missing plane with 10 on-board in Indonesia (http://www.news.com.au/world/asia/signal-detected-from-phone-of-pilot-linked-to-missing-plane-with-10-on-board/story-fnh81fz8-1227555897081)

[Nialler]

The fact that there is a functioning mobile which hasn't been used is not good news.

I can only hope that the phone's owner got separated from the phone on impact to the extent that the phone cannot be heard by any survivors. Even that scenario implies some violence.

Fingers crossed.

[peekay4]

Weather continue to hamper search efforts but local media is now reporting that the main wreckage has been found, very late afternoon Monday, Central Indonesian Time.

However since it's now nighttime, National SAR will not make a formal identification until tomorrow morning local time. No survivors can be expected at this time.

Surprisingly, the Minister of Transportation, Ignasius Jonan, said that the aircraft might have violated air law by deviating from the flight plan to "take a shortcut", and that he might pull Aviastar's operating license as a result.

He later clarified that such speculation came from Aviastar management.

Very unprofessional conduct all around. I did notice similar brash statements from the minister relating to the AirAsia QZ8501 accident.

DetikNews claims to have the first picture of the wreckage:

Ini Foto Pertama Puing Pesawat Aviastar di Pegunungan Latimojong (http://news.detik.com/berita/3036526/ini-foto-pertama-puing-pesawat-aviastar-di-pegunungan-latimojong)

http://usimages.detik.com/community/media/visual/2015/10/05/d6596531-f301-418f-b4ae-fabce8a9f453.jpg?w=780&q=90

[lomapaseo]

The photo (enhanced) is quite revealing. Is it of the subject aircraft or some other?

[WingNut60]

If it is indeed the Aviastar aircraft I can see where the minister is coming from.
Masamba Otter / CASA flights typically route west of that mountain group - less commonly east and down the coast.
Soroako flights tend to cross the island leg south of that range.
With peaks at or over 10,000 ft it's no place to be in a Twin Otter.


Reported location appears to be about 20 - 25 minutes SSW of Masamba

[troppo]

[QUOTE With peaks at or over 10,000 ft it's no place to be in a Twin Otter.
[/QUOTE]

Why not?

[peekay4]

@troppo

The -300's single engine service ceiling is not much above 10,000ft density altitude on a good day.

@WingNut60

IMHO it is inappropriate for the Minister to engage the press in wild speculation and to pre-empt the Safety Board's investigative work.

That's our job at PPruNe!!! :}

In Indonesia the Safety Board (KNKT) isn't completely independent as it should be. The Minister can completely replace the board at his whim (as he did so last month). It's like having the NTSB under the FAA -- lots of conflicting interests. Who's brave enough to contradict the Minister?

There have been recent calls by congress (DPR) to revamp the KNKT as a truly independent agency, with board members nominated by the President instead of selected by the Minister of Transport. Probably a good idea.

[anartificialhorizon]

Twotters service ceiling not above 10,000ft ....?

How do you think these aircraft get around in places like Papua? Over the tops?

[peekay4]

Read it again carefully: "single engine service ceiling".

[WingNut60]

Peekay4 : I agree completely - inappropriate for him to say it, but not inappropriate to think it.

As for service ceiling, not sure where that comes into it.
Unless the crew and passengers are all running on oxygen.

Normal assigned altitude for these flights is 7 - 8000 feet.
And stay well clear of that range of mountains; because you don't need to go that way.

Was PAX on a Merpati Otter when we did a single engine turn-back to UPG in that very region in the early 80's.
From 8000 we lost 2500 in the turn and got about 500 back.

I'll stand by my statement, IF that aircraft is really where it has been reported to be, then it's no place for an Otter, at least not while there are better alternatives.

[peekay4]

In Indonesia I believe you're allowed to fly up to 12,000 ft unpressurized without anyone on oxygen -- or 14,000 if the crew is on oxygen -- for 30 minutes.

The supposed crash site does appear to be in a direct line between the departure airport at Masamba and Makassar (UPG), the destination, not far from Rantemario peak.

Yet (unconfirmed) reports say the wreckage was found at 7,000 ft altitude. If the crew had intended to take a "shortcut" by overflying the highest mountain range in Celebes, one would think they would have been flying at a higher altitude. As India Four Two pointed out, Rantemario tops out at over 11,000 ft.

Of course it's also possible that they were flying higher, but lost altitude for some reason. Or the crew made a grave error and mistakenly flew direct Makassar.

Since all the passengers are from the Ministry of Transportation, this flight was basically a VIP flight. (Frontier / pioneer flights in Indonesian interior are paid for largely via government subsidies). Hopefully the crew didn't feel pressured to make an unsafe decision.

[WingNut60]

I am sure that it is possible to do the direct line to UPG in an Otter, but it's just not how it normally happens.

Most common routing would be out to the west of those mountains where the navaids are :- Rantepao, Makale, Enrekang
That track adds a few km and about 5-10 mins to flight time.

7000 feet is entirely consistent with common assigned altitude for these flights.

My guess (yes GUESS) is that he was 20 - 30 km east of favoured track for some unknown reason, in cloud or with limited visibility.
Lots of smoke around just now but shouldn't have been a problem at that altitude.
It'll all come out eventually.

Does PK-KBD ring a bell Peekay4?

[peekay4]

Not suggesting that it's the routine, but going by the current speculation that the crew might have taken a "shortcut".

Such speculation is supported on the basis of the wreckage location (directly in line to UPG) and timing -- at just 11 minutes after takeoff. The aircraft likely headed on a southerly direction almost immediately after takeoff.

But the shortcut speculation seems incorrect on the basis of the wreckage altitude (only 7,000 ft), unless maybe they intended to hug the coast until they can fly direct to Makassar, but then turned early.

Not familiar with PK-KBD accident... do you mean the Timika-Eranatoli crash? (PK-LTZ)

[WingNut60]

No. Just picking up on your pseudonym and location
PK-KBD (later PK-LTZ) was the old INCO -100