What is the ceiling of a Eurostar, carrying (say) 200kg payload, at ISA+25?
Is the temperature of the fuel important with Rotax powered engines (in the same way the Petersen STC for use of Mogas instead of Avgas specifies a maximum of 20C)
Yes, you would not fly anything on Mogas these days without getting vapour locks but I doubt this would happen in two different aircrafts at the same time otherwise many aircrafts in Europe would have been fallen out of the sky (not necessarily near the Alps)
Tough I would not discount midair collision? or fuel contamination issues? or just independent crash in terrain due to performance?
RIP, really sad for the whole group !
Ibra wrote:
Yes, you would not fly anything on Mogas these days without getting vapour locks
Ibra, would you mind clarifying this statement?
Peter wrote:
What is the ceiling of a Eurostar, carrying (say) 200kg payload, at ISA+25?
Their website gives a service ceiling of 19.6k ft. Presumably that’s at ISA, but even at ISA + 25, 9k ft shouldn’t be a problem as it would equate to roughly 12-13k.
Col de l’Arche is a Scenic place to fly over the mountain, what a sad story. Mountains are around 2500m but the pass itself is a wide area at 2000m with a steep climb from French side then descending toward Cuneo in Italy.
I flied all day today near this area and the wind forecast was calm, but we can never be sure, and there was a SIGMET for embed TS in this area.
@2greens1red the LAA has a nice summary on Mogas issues with hot temperature (applicable to Avgas as weel) but not sure how much of this is relevant to the accident?
On one Rotax TMG I used to fly taxi & power checks are done with electric fuel pump off to check that mechanical fuel pump is working and that mogas is not eveporating and cutting the engine (EV97 has rotax with electric fuel pump) but I doubt the issue with Mogas, tough hot topic of the moment, is that relevant…
Ibra wrote:
@2greens1red the LAA has a nice summary on Mogas issues with hot temperature (applicable to Avgas as weel) but not sure how much of this is relevant to the accident?
Thanks, Ibra. I’m up-to-date on Mogas issues, and the LAA advisory.
Vapour locks are a risk with fuel temp above 20C. But I don’t think “….you would not fly anything on Mogas these days without getting vapour locks” is accurate, and might mislead.
Hundreds of us fly with Mogas, and we don’t suffer vapour locks at the recommended temperatures.
My statement is a bit exagerated for all type of flying, when soaring locally mogas runs fine in TMG at 35C without any cuts but that is a glider and it is not going 6000ft tops of the Alps on hot days…
There are various limits on Mogas, but do we know these planes were using Mogas?
There is a 6000ft limit and the UK LAA operates a (rather bizzare) +20C limit on [some of?] its permits. See e.g. here and here.
ASN now has different wording so I edited the thread title.
Clearly these accidents have stirred up some concern, for the LAA sent out this email yesterday
From: Light Aircraft Association
Sent: 24 July 2019 14:15
Subject: Aircraft Owners – Hot Weather Warning
Dear LAA Aircraft Owner
Remember: Your aircraft’s performance, and therefore its behaviour, will change as the ambient temperature and pressure changes. These changes will affect all phases of flight and need to be taken into account by a pilot planning a flight.
More advice is provided in the Airworthiness Alert that we issued in August last year, and is still very pertinent.
Regards
Light Aircraft Association
Above LAA Mogas URL has been fixed.
