Now here is a report about a VFR trip EPKM – LFLY – EPKM. This time I am not building it around the sequence of events, but rather I am groupping my memories by improvised categories.
Background and rationale: The purpose of the trip was to visit caves in Massif du Vercors together with Ola, my wife. We wanted to do two, maybe three cave trips and read books/taste some nice French food in the meantime. I have already been flying with Mrs on a couple of occasions, both with and without children.
Lyon-Bron: Upon arrival at our destination
Aircraft and pilot: We flew in the first and only plane I own – one Fox Oscar, Piper Arrow IV, registration SP-EFO that I bought last year. The aircraft is some 43 years old, but in good shape and well equipped. I am flying the plane since March this year and have not been driving any Pipers before, T-tailed or not. My experience is on the order of ~400h TT, VFR only. Before the Piper I flew C150s, C172s, Tecnams P2002 and a vintage Beech Bonanza.
Route flown on the 2nd leg.
Routing and choice of airports: We wanted to stay somewhere around Pont-en-Royans, a little town we knew from our previous visit in the area (coming via CAT back then). The closest airfield is probably LFKE, but it is a little shortish and restricted: the VAC calls for familiarization/mountain rating. LFLG Grenoble or LFLS Isere are a natural second choice, both featuring favorable PIREPs in our database. In the end, however, ease of renting a car was the primary factor in my settling on LFLY Lyon-Bron. And for the planned caving trips it was absolutely vital to have a car at our disposal, due to sheer amount of equipment to be transported and remote locations involved. Although there are no rental businesses at LFLY Lyon-Bron, the CAT airport LFLL Lyon-Saint Exupéry is some 25 min away by Uber. Driving from Lyon to Vercors takes some 1.5h, which I thought was not bad.
Vercors countryside
Probably it could have been organized better if I spoke French. Alas, I just know a few critical phrases like L’addition s’il vous plait or maybe Location de voitures. Car rental businesses are few and far between in the Vercors countryside. Still, even if it is possible to find one close to a rural airfield, it would be incredibly complex for me to call them and make sure they are really open in the middle of holiday season…
Timing: For me it is actually a very important element in risk mitigation strategy. I struggle to avoid pressure for any particular departure/return date so that I don’t have to fly anywhere near dubious weather. It is of course difficult and sometimes simply cannot be done. While I have flexible arrangements at my work, the Mrs works as a teacher and her off-work days are set in stone. Thus two of our trips this year have occurred during the summer school break, and the third one during a 9-day (very) “long weekend” around a favourable constellation of national holidays in May this year.
Book reading day. No pressure.
To make this particular trip, we had a ~12 day window, during which we could count on the children and the dog being well taken care of. An additional constraint that dawned on me late was a car show being held on our home airport EPKM Katowice. Our Aeroklub was closed for a 10-day summer break, Saturday to Monday, so indeed it made hardly any difference that we rented out the airport grounds on one of the weekends… Well, almost. It may not have mattered for the casual renter, but it mattered for me! The show was on Sunday, with preparations starting on preceding Saturday – exactly the day when the said 12-day window started. I managed to negotiate the closure NOTAM wording, so that it was effective Saturday 9 UTC, instead of early morning. But it meant we either depart Sat morning or – had there been no weather – we would have had to wait until Tuesday. Just an example what kind of constraints can sometimes enter the equation out of the blue…
General weather outlook on the day of return
Weather: Rare luck! Starting exactly from that said Saturday, a spell of high pressure summer weather was forecasted, East to West across continental Europe. And Mother Nature stuck to the plan. We were able to embark on the journey exactly on the day when our window of opportunity opened – and use the remainder of that window as a buffer. We had no weather issues whatsoever, neither on the way there, nor back home. No real clouds, no rain, no thunderstorms and merely thermal turbulence at low level. The only inconvenience we encountered was a heat wave in France. On our departure, the Lyon METAR indicated 35 degrees C. I was asking tower for my clearance in the dark, sitting in an aeroplane still fully equipped with parking window shades. To stay relatively cool, we removed them carefully one by one – the windscreen shade went away just before starting the engine and the side windows shades we removed before taxi. Fortunately they are installed and removed from inside. The rear reflective shades stayed on the windows throughout all the way back home… and I don’t care if that was legal or not!
OAT = 36
Dispatch and planning: One is supposed to fly according to an Operational Flight Plan. I always produce it iteratively, beginning with an Orientational Flight Plan. To get one, I started with plotting straight line EPKM-LFLY in skyvector.com. That’s 628 NM, straight across München, Lake Constanz and Lake Geneva. I thought this routing was perhaps a bit “dense”- and close to high mountain peaks. So I added a waypoint at Basel. The rest was fine tuning to avoid crossing FIR and/or airspace boundaries for pointless 2 minute corner cuts. I ended up with EPKM REGLI BAXEV USUPA DOLUP AKINI WLD PELOG TITIX BLM REFEL TUFTA LFLY – that sums up to 643 NM, a ~8 minute detour compared to straight line. Not bad, but anyway not comfortably doable in one leg at any ground speed available to me (… it would have to be something like 185 kt on average). So I had another look at airports.euroga.org – and quickly EDMS Straubing popped up, boasting no hassle service and a recommended restaurant.
Regensburg in Germany, I presume
On the return day some mild thunderstorms could be expected near München, so I shifted the routing slightly to the north. Namely the route filed was: LFLY BULOL TUROM MB DEVDI GAGSI KOVAN EDTY Schwäbisch Hall, and from there ELVAG GOLMO RDG BARIX VAKLA TIBLA REGLI EPKM. This is some 666 NM, so 38 NM over straight line distance. But our return proceeding in the easterly direction, the winds were well in favour.
Weight, balance and fuel management: We took a lot of stuff along, including trekking poles and 250 m of 8.5 mm nylon rope. The bulkiest items were weighted with a fishing scale and amounted to 64,9 kilograms. I estimate the last minute stuff added an extra 5 kg. With full tanks it implied a takeoff almost at MTOM. However after the preceding flying I was short of ~5 gallons – so I decided not to top up to add some extra margin. Still, our fuel on board amounted to some 5h no-reserves at the most fuel hungry cruise mode, and I intended to refuel at every stop. Thus no careful fuel management was required this time. In the end we didn’t use the trekking poles and could have taken 100 m less cord. But that’s how life is, if you want flexibility.
Want to fly 2 people with gear? Buy a 4-seater…
Performance and issues: The previous longer trips I was flying over water, and thus determined to keep my reserves high. This time I could forget saving gas and test what happens at two levers forward (wide open throttle and full speed prop). The red lever was set 0 ROP almost all of the time. At 6000ft, the instruments reported a fuel flow of 10.2 GPH and a consistent TAS of 130 kt; maybe 131-132 if I fiddled with the balls a bit (* – the Fox Oscar has rudder trim and its analog turn coordinator gives slightly different indications than the digital ball on Garmin G5).
“WOT” cruise
We crossed TMA of Basel both ways – and other than that, moved in Class Golf or Echo airspace en route. It feels very reassuring talking to Czech and German FIS. The French are sure equally as helpful and polite, but my experience so far is they don’t always take pains to make sure the amateur pilot (ie. sub-professional R/T – sorry!) gets the message. It’s only French ATC that I had already asked two times this year to “SAY AGAIN? SLOWER PLEASE …”. This kind of conversation is representative:
Basle ATC: Are you familiar with Basle reporting points, sir? Can you fly Whiskey Alpha Whiskey Bravo due to traffic departing along runway axis?
FoxOscar: Affirm, we have the points on our map.
(silence… CAS boundary crossing in 20 seconds…)
FoxOscar: Are we cleared to enter class D airspace?
Basle ATC: Affirm.
Is anything wrong? No! You ask a question – get an answer – no problem. But I just consciously notice that I got a bit spoiled elsewhere … where admittedly there is less traffic. Anyway, both ways there was no question “if” we can fly through CAS VFR; in the parts of Europe I am flying, this seems to be a problem only in VERY busy airspaces. I am paraphrasing a bit, but on the way “there” the crossing went like this:
Basle ATC: Can you climb 8000’?
FoxOscar: Affirm.
Basle ATC: Climb 8000’ on QNH 1019. What is your intented routing?
FoxOscar: From present position to REFEL.
(5 seconds)
Basle ATC: We don’t have that point.
(5 seconds and – Eureka!)
FoxOscar: So… We continue on present heading?
(5 seconds)
Basle ATC: Approved.
Another crossing of Basle TMA
On the way back it was a bit more complex. We were asked to fly 3000’, contact tower, then make an orbit, report crossing the runway axis and so on. But it was more fun than hassle. We got a very nice view of an airliner taking off.
In flight experience: We now have consistent data indicating that descents make Ola feel very sleepy and/or sometimes unwell. It seemingly depends both on the TOD altitude and the rate of descent, but even mild descents from 8000’ are a nuisance. On the other hand, 6000’ seems quite fine; but then, if the terrain below is somewhat higher, there is turbulence – also a problem… At this point I am even considering buying a portable oxygen system. For me it is vital to keep my passenger(s) happy. If I loose them, I loose my rationale to fly.
We enjoyed delicious in-flight meal service prepared by Ola: stuffed tortillas, fruit chunks and coffee. Some technical remarks about the aircraft relevant to this trip are also in another thread.
The fuel stops: Very good, but… We stopped at EDMS Straubing and then, on the way back, at EDTY Schwäbisch Hall. The welcome, the service, the staff, the refuelling – all in perfect order.
- Do you have a noise certificate?
- Sure, but it’s in the aircraft. No worries. I’ll go and fetch it.
- You can use the bicycle!
Same story at EDTY:
- Do you have a noise certificate?
- Oh my … I am not learning…
- I beg your pardon?
- Will it be enough if I show you a scan on my laptop?
- Sure!
It was not critical… but we craved for lunch, especially on the way back. Nothing really fancy, just some salad and coffee would do. Alas, the Straubing restaurant closed for holidays exactly the day before we started the trip. We got decent coffee from the staff, but obviously no salad! Planning our return I devoted a good hour to looking up airfields in south-ish Germany featuring a restaurant. There are lots of them: EDFW, EDQH, EDQE, in town near EDQA… All (!) the restaurants, however, either open at 5pm or are closed for holidays. I gave up and settled for EDTY Schwäbisch Hall, that I have already visited twice before. It is merely 6 minutes driving from the (very nice!) town and the airport has four(!) cars available on site! These are provided by a carsharing business called App2Drive – you rent/return the cars self-service using a smartphone app. I have already been using “Traficar” in Poland and “rail&drive” in Austria and find this kind of service very convenient. So I have promptly sent my driving license scan and opened an account with app2drive – might come handy next time! I wonder if there are similar ways to cope with ground transportation in France…
Nice waterfall in Scialet de l’Appel
The caves: Vercors is renowned for caves. We have caves closer to us – in the Tatra mountains or in the Alps. But they are very hard core. Most of the entrances are far up in the mountains and moving within the caves is very demanding – involving lots of ropework and very often more equipment than the two of us could possibly carry. We like it and it is fun! But sometimes it is nice to go somewhere easier (but of course not too easy!). Hence Vercors. Lots of caves in France are suitable for half-day trips, as they are located close to motorable roads and feature a lot of horizontal development. There is also plenty of superb guide material available (albeit mostly in French) and – importantly – usually there is no need for a special permit to go underground.
On the way through Grotte des Ramats
We visited Scialet de l’Appel and then Grotte des Ramats. Both trips were exactly of the kind we had hoped for. Not too long, some pleasant climbs, many nice views, some water – though not too much. And of course, like always in the summer, it was pleasantly cool underground. We didn’t meet any other cavers. Our guidebook mentioned that Grotte des Ramats takes between 2 and 10 hours, but most people venture only as far as to the siphon (2 hours round trip). In fact we needed more like 4 hours to do “the miniumum”, but we took a lot of photos on the way and had a long picnic near the siphon. The siphon can be bypassed without diving – and according to the guidebook there’s a lot of beautiful cave to see beyond it. However, it seems even the bypass gets you toroughfully wet, as it leads through a short, flooded section that has maybe 15 centimeters of overhead air. That’s how we came to understand why “most people” don’t go there – and we skipped it as well.
A rope traverse in Scialet de l’Appel
It’s not all a bed of roses (in Grotte des Ramats)
Life on the surface: In the afternoon the air temperature reached 39 – 40 degrees C. We were extremely lucky with our accomodation. We lived in an old farm building converted to holiday apartments by an entrepreneurial, France-loving Brit. Thick walls and windows staying in shade all the time made the evenings and nights very comfortable.
Good morning, France!
We had very limited success tasting French cuisine. Very good memories of dining experiences from the previous visit I mentioned have been now overwritten by a struggle to fill our stomachs on evenings this time. On Saturday we should have dined in Lyon, as when we reached the countryside everyone was already closing. On Sunday we had a decent meal at Le Refuge du Phoenix in Échevis. On Monday – the book reading/rest day – we dined at Le Jorjane in Choranche, but that required waiting 1 hour for a table to become available. You may think we should have gone somewhere else, but try finding a restaurant open on Mondays in the Vercors countryside – or even in Romans-sur-Isère! On Tuesday we tried hard to learn from experience and attempted to reserve a table at La Source in La Chapelle-en-Vercors. However at around 4pm they were already fully booked for the evening. So we gave up and bought a lot of cheese at a local Intermarche…
Substitute meal
Closing remarks: Air transport is overrated. People here mention hassle at the airports or in the air, but there is even more hassle inherent to the fact that aeroplanes operate to and from runways. Returning from the trip, we left the apartment in Saint Laurent at 9am and reached home at 9pm. Of this time, we spent roughly 5 hours flying, which was very fun for me and fun enough for my wife. The rest – the majority of the travel time – was pure hassle: driving to the airfield, washing the rental car, returning it, refuelling the plane, moving other planes in our home hangar, driving home… We did a similar trip via CAT to MXP plus some cross-border driving in 2020 and it was in fact not much different. You just trade one type of hassle for another (like crowds at the airports, security, long waits at the boarding gate) – and loose flexibility as a side effect (ie. it’s difficult to postpone the trip if the weather is not good for caving). Still, if it were not for the aeroplanes, for us getting there would mean a 15 – 16 hour drive. And that is not counting breaks and assuming all goes well on the roads. It is not just “3 or 4 hours more”, it’s a full day of travel more and for us it kills the whole trip. Conclusion? We keep to flying.
Moving planes around & collecting the luggage upon landing
Hey @Mateusz, thanks for the report! Exactly the stuff I like to read about. Looks like you (and hopefully Mrs Mateusz) had a great time.
BSL is, for the traffic they handle, an extremely forthcoming airport. I used to fly outta there flying the line, and getting inpatient at the attention VFR traffic was getting… close to 6 years into retirement, I now appreciate their trying to accommodate attitude.
Looking forward to your next report(s) 
PS
You sure gotta update your C172 profile 
Hey @Mateusz! Interesting and novel way to write a trip report! Probably easier to read than the typical sequential form.
Even though your stops seemed hassle -free, having to do a fuel-stop does add a lot to the overall timeline, but also allows for some leg-stretching for your pax! Being able to make trips within the aircraft’s and its POB’s range simplifies the story making it closer to a half-day event vs a whole-day event. Of course some of the ground-logistics are independent of mode of long-range transport…you still need to get a holiday place, some rental car or public transport for driving around, and those things do take their time. As you say: ideal if time is not a factor.
I do like the fact you care more for your pax than for the rest of your flying while in flight…keep it on!
Performance-wise, I wonder if the numbers reported are good and how they compare to book and other examples of the type. We used to fly a C177RG (similar power) and cruise at a similar setting was 18KTAS faster ROP, 10KTAS faster 70LOP (@9GPH @7000ft), which is a lot of delta. Not knowing your type, I’d think it could fly faster at that high power setting (I would anyway advise to fly either ROP or way LOP at such high power). I note you fly the 2-blade prop which helps (3-blade is a usual speed-robbing offender for this power range). Perhaps some slight miscalibration of the ASI, or some misrigging on flight controls or gear doors? Or perhaps simply the high weight? I do read 134KTAS in the pic you posted, both in your TAS calculator and my E6B using 6200prAlt and 13OAT… don’t hesitate to disregard the flight-test engineer in me if you think all is in order!
BTW quick and good thinking to change your routing waypoint request for a heading!
On the ground hassle, too bad you need to move several aircraft before you can park yours, but at least you have place to park, and best of all you can move your car next to it saving otherwise cumbersome gear transportation.
Great trip! Have you added airports experience to our airport database?
Performance-wise, I wonder if the numbers reported are good and how they compare to book and other examples of the type. (…) don’t hesitate to disregard the flight-test engineer in me if you think all is in order!
Yes, it would be great to compare against another NA Arrow IV! Difficult to do by naiive googling (difficult to refine the search to distinguish between the Turbo and NA, and also some of the PIREPs that do appear do not give altitude).
It’s the first aircraft with such sophisticated instrumentation that I am flying. I tried “100 ROP” on that trip and arrived at a slight loss. Until now I have thought maybe I wasn’t serious enough about it … maybe I have not given it enough time to settle … or maybe I should have done it setting 2500 RPM, as prescribed in the cruise setting table … maybe it’s these 5 fpm climbs … or perhaps the performance difference between “0 ROP” and “100 ROP” is a bit overrated. But your remarks made me look again at my photos and the POH… and now I am even more troubled.
Here’s basic data at 0 ROP cruise regime. The propeller is not fully fine.
0 ROP, OAT 13, 6000’, IAS 117. QNH1013. FF=10.3, MP=24.9, RPM=2550, DA=7156, TAS=130
Later on the same day, 100 ROP. The photos are 25 seconds apart.
92 ROP, OAT 17, 6050’, IAS 115. QNH1013. FF=12.0 GPH, MP=25.0, RPM=2490, DA=7667, TAS=129
No TAS improvement over 0 ROP. Would a 60 RPM drop make that big a difference? Did I touch any of the levers between the photos? Can’t remember now.
Two minutes later, returning back to 0 ROP.
0 ROP, OAT 17, 6000’, IAS 118. QNH1013. FF=10.0 GPH, MP=25.3, RPM=2560, DA=7606, TAS=132
Maybe it hasn’t settled yet.
Now “sitting in my armchair” I am having a closer look at the EGTs for individual cylinders. On the “92 ROP” photo they read: 1384, 1354, 1368, 1309. On the “two minutes later, 0 ROP” photo we have: 1516, 1502, 1531, 1471. Differences for individual cylinders: +132, +148, +163, +162. What does it tell me? I don’t know… Am I moving the red lever too fast?
This is on another day (the way back). Now I am lower. TAS should be worse. Prop lever full way forward.
0 ROP, OAT 18, 5000’, IAS 123. QNH1020. FF=11.1 GPH, MP=26.3, RPM=2640, DA=6497, TAS=135. What the hell? Some transient effects? Or simply better aspiration of the engine due to lower altitude – manifesting in higher MP.
Trying 100 ROP again later during that day. The photos are around a minute apart. Note the GS – nice wind!
100 ROP, OAT 14, 6000’. IAS maybe ~121. QNH1019. FF=12.5 GPH, MP=24.8, RPM=2650, DA=7130, TAS=134.
Again let’s look at individual cylinders. We have: 1543, 1508, 1527, 1471. Pretty similar to the previous “0 ROP” situation. The numbers for “100 ROP” are now: 1434, 1398, 1413, 1358. Differences: +109, +110, +114, +113. That indeed looks closer to 100 ROP than these few days ago. But still. I hoped maybe the individual differences will run wild, like say, +200, -100, +80, -160, maybe proving the whole injection system is daft. But no.
Yes! – the POH! What does it say? Need to look up the pressure altitude. For the last quoted parameters that’s some 5800’
It definitely says at this fuel flow I can expect the plane to go faster.
It also says – not seen on the screenshot – that FF 9.6 and 10.8 GPH constitute a 65% power setting for economy and performance cruise mode respectively (0 or 100 ROP). They give two examples, both at 6000’ and 10 degrees C and 65% power. Economy cruise (0 ROP) in this circumstances, they say, yields 126 KTAS. At the same time, running the engine 100 ROP should result in 133 KTAS.
So, at 65%, adding +2.2 GPH “with the red lever” you should get +7 KTAS. The relations for 75% power cruise look similar. But it just doesn’t work!
All performance graphs and examples in POH are at MTOM.
Let’s return to 0 ROP (40 minutes later). Note the ball is now in center at the G5.
0 ROP, OAT 13, 6100’. IAS ~120. QNH1019. FF=10.4 GPH. MP=25.5, RPM=2650, DA=7078, TAS=133.
For some comparisons, the following photos are from the Bornholm trip. These flights were at 8000’ though.
0 ROP, OAT -1, 8000’, IAS 104, QNH1013. MP=21.8, RPM=2250,FF=7.4 GPH
That is DA=7991 and TAS=117. And 15.8 NAM per gallon as compared to 12.6 @130 KTAS/10.3 GPH.
This one is a bit unnerving – why bother with +4 extra kts, if that needs so much more fuel?
0 ROP, OAT -5, 8000’, IAS 113, QNH1013. MP=23.2, RPM=2320. FF=8.8 GPH
That amounts to DA=7512 and TAS=126. And 14.3 NAM per gallon.
Weight-wise I am comparing very similar situations. I mean of course the fuel gets burned as I go, so it’s always a slightly different weight. But every flight “quoted” on the photos above started with a takeoff at MTOM or almost MTOM.
What could I be doing wrong? Sub-POH performance – yes – maybe it’s misrigging, maybe ASI calibration or maybe both of the balls are lying. But almost no difference between 0 and 100 ROP except in the fuel flow?
Dan wrote:
Exactly the stuff I like to read about.
Antonio wrote:
Interesting and novel way to write a trip report
Thanks guys for the positive feedback :)
Emir wrote:
Have you added airports experience to our airport database?
Not yet but I am a fan of the database and shall do it! I am waiting for an invoice from LFLY. And both EDMS and EDTY entries will surely benefit from a recent update.
@Mateusz looking at the figures and doing a bit of mental arithmatic your TAS seems pretty coherent with your IAS. Your TAS will change with altitude and temperature wheras it is your IAS and fuel flow which will change by aircraft attitude, mixture and prop settings. IMO it is the IAS you should be building your engine settings around.
gallois, roger, but… This time it’s not only about doing the best for the engine, but more about what Antonio mentioned. There is aircraft range and then there is “POB’s range”. In my case the latter is much smaller. If I am witnessing just an instrumentation issue, then never mind. But if there is some extra TAS to be found … then extra few knots surely could help sometimes. For example, my reasoning if I were to travel 500 NAM could easily go like this:
But this applies only to some limited borderline cases. However they do exist: I am considering visiting ESSW Västervik again and that’s 462 NM from EPKM straight-line.These extra knots, if they are there at all, are definitely not a critical thing (vide my remarks on hassle in general). But it’s not just being picky about the numbers on the fancy screens. There are real life implications!
