Tag Archives: aircraft

Review of Boeing Current Market Outlook 2015

Just ahead of Paris air show, Boeing Commercial published its yearly update of the Current Market Outlook (CMO) for the next 20 years of commercial aircraft market (2015-2034).

I have just compared the figures for passenger aircraft of the last two years’ CMOs:

CMO 2015 vs 2014 comparison.

CMO 2015 vs 2014 comparison.

Some comments to it:

  • You can see that the total number of new aircraft delivered has slightly increased from 35,930 to 37,130, a 3.3%, which is consistent with the 4.9% traffic increase (1) that Boeing predicts (2).
  • The volume (Bn$) increases by a larger percentage, 6% (320Bn$)… this is due mainly to the increase in:
    • single-aisle aircraft expected sales in volume (8%, +210Bn$) and aircraft (+210), and
    • small wide-body segment with 230 more aircraft (+5%) and an increase in volume of 100Bn$ (+9%).
  • Two years ago, I wrote about a sudden change between CMO 2013 and CMO 2012 of the mix in wide-bodies; in this respect, CMO 2015 is consistent with last year’s one, showing simply a slight increase in demand for both sub-segments.
  • Interesting to note how Boeing continues to downplay the large aircraft segment (-16% in terms of number of aircraft) at the moment when a A380neo is discussed.

This year study’s figures and presentation focus on single-aisle (737 MAX, “fuelling forecast”) and small wide-bodies (787, “re-shaping long-haul marketplace”), the products to be pushed by the sales force.

Find below the nice infographic [PDF, 2.1MB] that the guys from Boeing have put up together:

Boeing Commercial Aviation Market Forecast 2015-2034 infographic.

Boeing Commercial Aviation Market Forecast 2015-2034 infographic.

As always, I recommend going through the CMO, as you can learn a lot about the business: from global numbers, to growth, traffic figures, fleet distributions, forecasts, etc… You may find the presentation [PDF, 3.8 MB], a file [XLS, 0.6 MB] with all the data or the full CMO report [PDF, 6.5MB].

For a comparison between this CMO and the respective Airbus’ GMF we will have to wait until after the summer, when Airbus publishes its update. Until then, find here the comparison based on 2014 market studies.

This year together with the CMO, Boeing provides two interesting papers from a couple of years ago: Key Findings on Airplane Economic Life [PDF, 0.3MB, dating from August 2013] and A Discussion of the Capacity Supply -Demand Balance within the Global Commercial Air Transport Industry [PDF, 0.6MB, dating from August 2013].

(1) Traffic increased measured in RPKS (revenue passenger kilometers) in billions.

(2) These two ratios, 3.3% fleet demand and 4.9% traffic growth, point to an implicit increase in the average size of the aircraft in fleet and / or a higher utilization of the aircraft (higher availability).

(3) Find the reviews I wrote comparing 2014 CMO with 2013 CMO and 2013 CMO with 2012 CMO.

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Musée Espace Air Passion (Angers)

In the last post I described the Fly Out to Les Châteaux de la Loire that we made the last weekend. In that post I mentioned that we visited the museum Espace Air Passion in Angers airport. This post will be dedicated to that beautiful museum.

This museum is owned and run by an association, the “Groupement pour la Préservation du Patrimoine Aéronautique” (GPPA), created back in 1981 by a group of friends around the project of restoring an old aircraft (a jewel) from René Gasnier, a local pioneer of French aviation who flew in 1908 along 1km in an airplane built by himself. That airplane is the first one you get to see in the museum:

Rene Gasnier III, built in 1908, restored in 1988.

Rene Gasnier III, built in 1908, restored in 1988.

René Gasnier built his first airplanes between 1907 and 1908. This model, the III was built in 1908. As you can see it was made of wood and cloth. It mounted an Antoinette engine with 8 cylinders in V, with a power of 48hp, wingspan of 10m, less than 500kg at take off. It took the enthusiasts of GPPA over 1000 hours to restore it.

This airplane is surely not the only unique piece of the museum. Take a look at the following two airplanes.

The Gérin “Varivol”, built in 1938 (by the Compagnie Française d’Aviation), was based in the concept of using moving wings which extended themselves increasing the wingspan at the time of take-off when more lift was needed and reducing the wingspan to decrease drag at cruise. A prototype was successfully tested in the wind tunnel of Chalais-Meudon in 1946, however the actual airplane seems to never have flown. Had it flown, it was to have a cruise speed of ~455km/h while only 92km/h for landing speed. The wings were to be extended/retracted 2.75m per side out of a total retracted wingspan of 8.10m.

Alerion Riout 102 T.

Alerion Riout 102 T.

Built in 1937 by René Riout (at the workshop of Louis Breguet) with duralium, the 102 T explored the concept of flying by batting its wings (4, two at each side of the fuselage). During its test in 1938 when the pilot increased the engine regime up to around 4500rpm, after a few seconds, the observers saw torsion vibrations in the tip of one the wings before it broke, closely followed by the other 3 wings. It was then dismounted and forgotten till 2005 when the restoration at GPPA started.

This reminded me of a quote attributed to Igor Sikorsky that goes like:

Our engineers have determined that aerodynamically, the hummingbird shouldn’t be able to fly, but the hummingbird doesn’t know it so it goes on flying anyway.

Another oddity of the museum is one of the only two prototypes (1) ever built of the Moynet Jupiter (designed by André Moynet) which had the rare configuration of two push and pull engines, one in the front and one in the back of the fuselage. It was never sold to any customer, but it flew for the first time on December 17, 1963 (60 years after that glorious day in Kitty Hawk).

Moynet Jupiter.

Moynet Jupiter.

The museum has these other two sailplanes which have been declared patrimoine de l’aviation française due to the records they collected in their high time, the Caudron 800 Épervier and the Avia 40P:

We also enjoyed the visit to the workshops where they restore the fuselages and the wings. Take a look at the pictures and notice the wood and the cloth. Forget about those pictures the next time you get onboard a general aviation airplane.

We were given a guided tour by two members of the association, their explanations, anecdotes, connection with French famous pilots (including former Airbus’ test pilots) were invaluable. On the other hand, the audience couldn’t have been more responsive. Take a look at the pictures above: scores of years of aerospace engineering experience (flight testing, training), thousands of flying hours as pilots, real aviation geeks at its best.

The museum also has playing area for children, a MH-1521 Broussard for children (an adults) to get on and play, and some other beautiful aircraft including a Caudron PC431 Rafale, a Morane Saulnier 505, a Piper L4H Grasshoper, or the car Marcel Leyat Helica… see them below:

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(1) The other prototype is at  the Musée de l’Air et de l’Espace, at Le Bourget.

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Airbus backlog at end 2014 into perspective

Last Friday, Airbus Group announced its 2014 full year financial results at a press conference in Munich (Germany). You can find here [PDF, 785KB] the presentation used at the conference. In general, the results have been very positive in most metrics. There is one that in my opinion especially deserves attention, see it bellow:

AIRBUS 2014 results - backlog.

AIRBUS 2014 results – backlog.

Airbus has a record backlog of 6,386 civil aircraft.

In 2014, Airbus delivered 629 commercial aircraft. That is why, in the presentation it is stated “> 10 years of deliveries”. In essence, one may see it as if Airbus airplanes were sold out for the next 10 years! Of course, that is not the case for all product lines (think A330, A380) and will not be the case as a production ramp-up is announced in the A320ceo line.

Nevertheless, to put it into perspective, I wanted to compare this backlog to the historical aircraft deliveries of Airbus (which can be found here). Since its first delivery, an A300B2 back in May 1974, through the end of January 2015, Airbus had delivered 8,921 aircraft. With the information of yearly deliveries I compiled the graphic below, yearly per model and cumulative deliveries for all models combined.

AIRBUS deliveries through January 2015.

AIRBUS deliveries through January 2015.

Take a look at the cumulative deliveries.

On the occasion of the 8,000th delivery, on August 2013 (an A320 for AirAsia) Airbus published an article making a review of all the main delivery landmarks.

  • the 1st delivery, in May 1974, an A300B2.
  • the 1,000th delivery, in March 1993, an A340-300,
  • the 2,000th handover, in May 1999, an A340-300,
  • the 3,000th delivery, in July 2002, an A320,
  • the 4,000th delivery, in September 2005, an A330-300,
  • the 5,000th delivery, in December 2007, an A330-200,
  • the 6,000th delivery, in January 2010, an A380,
  • the 7,000th handover, in December 2011, an A321,
  • the 8,000th delivery, in August 2013, an A320 featuring Sharklets,
  • the 9,000th delivery… somewhere in the Spring 2015.

You can see that since the first delivery in 1974, it took Airbus almost 19 years to deliver the first 1,000 aircraft.

It took over 35 years to deliver the first 6,000 aircraft. That is what today it has as backlog…

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Boeing list prices increases vs. discounts increases (update for 2014)

In a previous post I updated the estimate of what is the average discount Boeing applies when selling its commercial airplanes using 2014 data of list prices, deliveries and reported revenues. The figure I came up with was a 47% discount. I included the following graphic showing the discount evolution:

Boeing Average Discount Evolution, through 2014.

Boeing Average Discount Evolution, through 2014.

Last year, seeing the increasing trend of average discount together with knowing the fact that Boeing regularly increases list prices triggered the following question: Have Boeing airplane discounted prices increased, decreased or stayed constant in the recent years? I set out to answer this question using the estimated average discount of each year (1) from the graphic above.

The Boeing list prices (LP) (2) can be found here. I have been recording those prices for years and thus have a table with the evolution of list prices for each model year by year. The following step is to apply the average discount estimated for each year to then-year list prices, to get the estimated discounted prices (EDP) (2) per model. Thus, a table can be built for the last 6 years.

You can find below the result for the best-selling aircraft during previous years: 737-800, 737-900ER, 777-300ER and 787-8. Together these 4 models amounted to over 640 deliveries in 2014 or 89% of the total 723 airplanes Boeing delivered in 2014.

Boeing List and discount Prices evolution table, 2008-2014.

Boeing List and discount Prices evolution table, 2008-2014.

In the table above I included in black figures what have been Boeing list prices of these models in the past years (as reported in their website) while I marked in blue the figures which are estimated, using as a departure point the calculated averages discounts per year (also included in blue in the table). I included as well the list prices year-on-year change as a % of the previous year list prices, per model.

The average list price increase included at the bottom line is computed with the information of all Boeing models (19 in 2008 and 20 in 2014, though different ones (e.g. last year addition of 777-8X and 777-9X), a total of 26 different models along this period), not only the 4 included in this table.

You may see in the table above that after not increasing prices in 2009, Boeing has steadily increased them in 2010 (6.3%), 2011 (4.7%), 2012 (6.7%), 2013 (1.9%) and 2014 (3.1%). However, if you take a look at the blue figures in the same table you will notice that prices of 2014 are between 2010 and 2011 price levels for all 4 models! That is, the widely announced yearly list prices increase has been yearly offset by a discreet (not-announced) increase in the discounts applied to the sales of airplanes. Thus, the pricing power of Boeing has remained barely constant during the last 5 years. You may see it better in the graphic below:

Boeing List & discount Prices evolution graphic vs. inflation in USA (through 2014).

Boeing List & discount Prices evolution graphic vs. inflation in USA (through 2014).

The graphic shows the price evolution for each of the 4 airplane models selected, taking as a reference their list and estimated discounted prices in 2008 (indicated as 100%) and also the evolution of inflation in the USA (3) in purple, to reflect the evolution of real prices (i.e. accounting for inflation). List prices are shown with straight lines, versus dashed lines used for estimated prices. Each pair of prices for each aircraft is presented in the same color for easier identification. Some comments to the graphic:

  • Through continuous increases, 2014 list prices were between 21% (737 and 777) and 31% (for the 787) higher than in 2008.
  • However, due to increasing discounts from 38% in 2008 to 47% in 2014, the increase in list prices is almost entirely offset (especially for 737 and 777, just 4% above 2008 levels).
  • 2014 discounted prices are below 2011 discounted prices for all models except 787.
  • If compare the evolution of prices vs. the US inflation (general prices in 2014 being 10% higher than in 2008), we see that:
    • Boeing actually lost pricing power in both the 737 and 777, which are cheaper in real (inflation-adjusted) discounted terms in 2014 than they were in 2008 (about 6% cheaper).
    • Only the 787 has been able to keep up the pace of discount escalation and inflation.

(1) There is no way to know the real price and discount that Boeing applies in each sale, as it will depend from customer to customer (American Airlines -AMR- or Fedex) and from model to model (737-800 or 787-8). There where competition is tougher, discounts will be higher. However, the estimates I have made are an average of all Boeing aircraft sold in a given year.

(2) Both list prices (LP) and estimated discounted prices (EDP) are expressed in then-year dollars.

(3) US inflation series since 2008: -0.4% (2009), 1.6% (2010), 3.2% (2011), 2.1% (2012), 1.5% (2013) and 1.6% (2014).

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Boeing discounts detailed calculation, 2014 vs. 2013

Last years I have published in the blog  some posts (1) dedicated to show what was my estimate of the average discount Boeing applies to its commercial airplanes. I included in those posts the rationale used for the calculation. Find here the post related to the calculation of the discount based on 2014 data of Boeing Commercial Airplanes revenues, deliveries and list prices.

In 2014, I included in another post a simplified table (2) with the calculation comparing 2013 simplified result versus 2012. In this post I wanted to update that table with 2014 figures in comparison to those of 2013:

Boeing discount detailed simplified calculation: 2014 vs. 2013.

Boeing discount detailed simplified calculation: 2014 vs. 2013.

In the table above, you may find for both 2014 and 2013 Boeing reported deliveries per model and Boeing published list prices per model (3) and Boeing Commercial Airplanes reported revenues.

What is then estimated? Boeing Commercial Airplanes services revenues (these are deduced from financial reports reported information), Boeing Commercial Airplanes platforms revenues (derived from the previous figure) and the average discount; this is calculated from the difference between estimated BCA platforms revenues and what should have been that figure had the airplanes been sold at list prices.

Results: average discounts of 46.3% in 2014 and above 46.2% in 2013, though nearly the same.

(1) Find here what is becoming a “body of knowledge” on Boeing discounts: estimates calculated for 20142013201220112010 and 2009; a review of the French portal Challenges.fr of aircraft discounts prior to Le Bourget airshow of 2013; aBombardier’s CEO statement on what is known in the market as the Boeing discount; Boeing Commercial Airplanes president Ray Conner speaking about the more aggressive pricing they are being forced to offer.

(2) I refer to this table as “simplified” as it excludes from the calculation the potential influence on yearly revenues (note, not cash flow) of down payments linked to orders received in then-year versus orders received in previous years for aircraft delivered in then-year.

(3) Two assumptions are needed: 737-800A transfer prices from BCA to Boeing Defense Space & Security for the P-8 (for simplicity assumed to be the same as the 737-800 price) and for the 737-based business jets (for simplicity assumed to be the same as the 737-900ER).

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Boeing commercial aircraft discounts (update for 2014)

Few days ago, Boeing released 2014 results [PDF, 838KB]. The company reported revenues of over 90.7bn$ (59.99bn$ for the Commercial Airplanes unit), 723 commercial deliveries and 1,432 net orders for its commercial aircraft. All these were widely reported by the media and mean a great year 2014 for Boeing (with increases in these metrics from 6 to 12%).

Last years, I wrote in some posts (1) what was my estimate of Boeing discounts: the relation between what is announced by the press, what appears in its list prices and sometimes as backlogs and what it is indeed computed into the profit and loss account. In this post I wanted to update, if necessary, the figure I calculated for the average discount of Boeing.

Most of the necessary information can be found in its website. Boeing list prices can be found here.

The number of gross and net orders (after cancellations) year by year can be found here.

Last year deliveries can be found in the report of financial results (or here). From there we can also deduce the figure of Boeing Commercial’s sales of services. That is not directly reported but can be deduced (all Boeing services-related sales are reported as well as Boeing Capital Corporation division and Boeing Defense’s “Global Services & Support” unit)

As in the previous years’ post:

  • I needed to make one assumption: new orders come with a 3% down payment in the year of the booking, while the remaining cost I assumed that was paid on the year of delivery (for simplicity I didn’t consider more intermediate revenue recognition milestones linked to payments, the 3% figure was taken from the AIAA paper “A Hierarchical Aircraft Life Cycle Cost Analysis Model” by William J. Marx et al.). (2)

Having put all the figures together, the calculation is immediate. Boeing Commercial Aircraft revenues in 2014 (59.99bn$) are the sum of:

  • the discounted prices times the delivered aircraft in the year (including possible penalties from delays),
  • less the down payment of the current year delivered aircraft, as the down payment was included in previous years results,
  • plus the down payment of current year net orders (this year’s calculation includes 737 MAX and 777X orders),
  • plus services revenues (about 0.7bn$ from the commercial aircraft unit – calculated, not reported).

The discount figure that minimized errors last year was 47%. Using this figure, the error obtained this year in relation to Boeing Commercial Aircraft reported revenues is -0.2%. The best estimate for last years average discounts were: 47% for 2013, 45% for 2012, 41% for 2011, 39% for 2010 and 38% for 2009.

The updated figure (which minimize errors for 2014 down to -0.2%) for the discount for Boeing commercial aircraft is 47% (3).

Boeing Average Discount Evolution, through 2014.

Boeing Average Discount Evolution, through 2014.

The discounts seem to be stabilized around 45-47%.

This discount figures and their evolution reflect that Boeing’s list prices and their continuous increases cannot be enforced in the contracts nor in escalation formulas.

Final note: I received a comment suggesting to review whether the discounts are in effect on Boeing side or in the engine manufacturers side. Unless we had the information of actual contracts, there is no way to calculate that from published information. Nevertheless, whether Boeing or engine manufacturers, the fact is that there is discrepancy of up to 47% between what Boeing announces as their list prices for commercial aircraft and backlog figures (in volume) and what it actually receives as income (revenue).

(1) Find here what is becoming a “body of knowledge” on Boeing discounts: estimates calculated for 20132012, 2011, 2010 and 2009; a review of the French portal Challenges.fr of aircraft discounts prior to Le Bourget airshow of 2013; a Bombardier’s CEO statement on what is known in the market as the Boeing discount; Boeing Commercial Airplanes president Ray Conner speaking about the more aggressive pricing they are being forced to offer.

(2) Three years ago, I received a comment from the analyst Scott Hamilton on the level of downpayments. He mentioned they could reach up to 30%. I tried this time to compute the calculation using that input, though the figures of discounts to be applied each year to minimize errors would have to be even higher, close to 60% (!), thus I stayed with the 3% used in the above-mentioned published paper to stay on the conservative side. On the contrary, if we assume that downpayments have no influence in the revenue recognition (as another comment indicated last year), but only in the cash flow, the discount figure would slightly decrease (about 1%). The issue is not so much the size of the downpayments, whereas how much of those, if any, are recognised as revenues.

(3) I find this trend of continuous increases in Boeing discounts in line with bothChallenges.fr report and Ray Conner’s mentions of aggressive pricing last year, both referred to in note (1).

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Swiftair MD-83 EC-LTV, BEA interim report

Some weeks ago I read the first interim report from the “Bureau d’Enquêtes et d’Analyses” (BEA) on the accident suffered by the Swiftair MD-83 matriculated EC-LTV on July 24th in Mali (find the report here, PDF 5.2MB). The last 1’30” of that flight must have been scary.

Take a look at the records of altitude, attitude, bank angle:

EC-LTV parametres

MD-83 EC-LTV parameters (2014, Mali).

Probably you are familiar with this other graphic that has appeared in the press:

EC-LTV trajectory worked out by BEA from FDR.

EC-LTV trajectory worked out by BEA from FDR.

Today, at lunch while on a training course, I had the chance to discuss about the accident with the course instructor (a retired former Airbus senior vice president in customer services) who pointed me at a similar accident undergone by a MD-82 HK-4374X in Venezuela in August 2005.

I went to the BEA website to check for the report of that other accident (here, PDF 20MB, in Spanish). While the investigation of the EC-LTV will most probably reach to the conclusions of the root causes of the accident, the are many similarities between the cases:

  • Hot weather conditions (ISA+10 or above, that is temperatures not below -30 degrees at FL31),
  • proximity of thunderstorms,
  • use of anti ice (inducing a penalty measured in about 3,000ft penalty for available engine thrust),
  • autopilot engaged in “Speed on Thrust” mode in “Altitude Hold” (making the aircraft pitch upwards when losing speed due to the lack of available power at FL310 due to hot weather and use of anti ice),
  • engine EPR close to maximum values for both engines (followed by a oscillations when the airplane starts to lose speed),
HK-4374X parametres.

MD-82 HK-4374X parameters (2005, Venezuela).

The report of the 2005 accident included a study from NASA and a presentation by Boeing then chief pilot covering similar incidents and showing a 2002 Boeing Flight Operations Bulletin warning flight crews of this kind of situations.

Boeing Flight Operations Bulletin MD-82-02-02A.

Boeing Flight Operations Bulletin MD-82-02-02A.

I’m looking forward for future reports from the BEA to see what are the findings they reach.

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Airbus vs. Boeing, comparison of market forecasts (2014)

Yesterday, Airbus released the new figures of the 2014-33 Airbus’ Global Market Forecast (GMF, PDF 7.5MB).

In previous years, I have published comparisons of both Airbus’ and Boeing’s forecasts (Current Market Outlook, CMO, PDF 5.3MB). You can find below the update of such comparison with the latest released figures from both companies.

Comparison of Airbus GMF and Boeing CMO 2014-2033.

Comparison of Airbus GMF and Boeing CMO 2014-2033.

Some comments about the comparison:

  • Boeing sees demand for 9% more passenger aircraft (excluding regional a/c) with a 10% more value (excluding freighters). The gap is closing, as in previous years Boeing forecasted up to 14% more aircraft.
  • In relation to last year studies, Airbus has increased demand by ~2,000 aircraft whereas Boeing by ~1,000.
  • Boeing continues to play down A380 niche potential (59% less a/c than Airbus’ GMF). This year, both companies have reduced in about 100 units their forecasted demand for the VLA segment.
  • Both companies’ forecast for the twin aisle segment is nearly identical: 7,260 aircraft. The mix between small and intermediate twins varies, 700 units up and down. However, Boeing’s wide-bodies mix is not to be taken as engraved in stone, see the erratic trend in the last years here.
  • On the other hand, Boeing forecasts about 3,600 single-aisle more than Airbus (the gap has closed in 800 units this year). The largest part of the difference comes in the single-aisles over 175 seats (A321, 737-9).
  • In terms of RPKs (“revenue passenger kilometer”), that is, the number of paying passenger by the distance they are transported, they see a similar future: Airbus forecasts for 2033 ~14.5 RPKs (in trillion) while Boeing forecasts 15.5 RPKs.

The main changes from last year’s forecasts are:

  • Both manufacturers have increased their passenger aircraft forecast, ~2,000 a/c Airbus and 1,000 a/c Boeing,.
  • Both manufacturers have increased the value of RPKs in 2033  (about 5-7%).
  • Both manufacturers have increased the volume (trn$) of the market in these 20 years, about 6.7% Airbus (to 4.4trn$) and 5.7% Boeing (to 4.86trn$) (excluding regionals and freighters).

Some lines to retain from this type of forecasts:

  • Passenger world traffic (RPK) will continue to grow about 4.7% per year (5.0% according to Boeing). This is, doubling every ~15 years.
  • Today there are about 16,855 passenger aircraft around the world (according to Airbus), this number will nearly double in the next 20 years to above 30,555 a/c in 2033 (over 33,000 as seen by Boeing).
  • Most deliveries to go to Asia Pacific, 39% or over 12,200 passenger aircraft
  • Domestic travel in China will be the largest traffic flow in 2033 with over 1,500bn RPK, or 11% of the World’s traffic.
  • Over 12,000 aircraft will be retired to be replaced by more eco-efficient type.
Trips per capita vs. GDP per capita (source: Airbus GMF).

Trips per capita vs. GDP per capita (source: Airbus GMF).

As I do every year, I strongly recommend both documents (GMF and CMO) which provide a wealth of information of market dynamics.

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Refuelling or not refuelling?

Last week, I took my brother and sister onboard of one of my flight lessons. Ahead of the flight I reminded my instructor that I would bring them along and asked what flight route should I prepare. His response: “prepare the weight and balance report, the destination will be a surprise”. And so I did.

For those not initiated, each aircraft has a defined maximum take off weight (MTOW). Before the flight, the pilot needs to ensure that the aircraft will be below that weight. On top of that, the centre of gravity must be within certain limits. That is the weight and balance (1).

For a small simple aircraft like the Robin DR-44 we flew, it is a rather easy calculation that can be done with a pencil. See in the image below two ways of calculating it: making the numbers or using the graphic at the bottom of the image.

Weight and balance report for Robin DR-44.

Weight and balance report for Robin DR-44.

Let’s review the numbers. We flew the DR-44 with immatriculation F-GSRR, which empty weight is 616kg. I estimated that the instructor and I, fully dressed and with headsets would weight ~160kg. My brother and sister behind, another 160kg. Baggages: I almost emptied mine and weighted it, 2.5kg. My instructor’s one is rather heavy, I assumed that together they would be 10kg. Principal fuel deposit: 110L of Avgas, with a density of 0.72kg/L, 79.2kg. Another 50L for the reserve deposit, 36kg.

Summing up: 1,061kg.

You can read in the image that the maximum take off weight for the plane is 1,000kg…

What to do then? Clearly, the aircraft is a given, so weight shall be reduced from somewhere else. But, from where? Either we left someone on ground or reduced baggage weight (my instructor left his and brought along only a book with aerodrome charts). However, baggage weight contributed only 10kg to the initial calculation. I then calculated: what is the maximum fuel we can carry?

Forget the reserve deposit: 36kg less. Let’s go with the principal deposit. What is the maximum fuel volume that would enable us to be within the 1,000kg limit? It would be somewhere about 80L (vs. the capacity of 110L of the deposit).

When I arrived to the aerodrome, I came with the message to my instructor: “Thierry, we can only carry 80L, if the plane is filled up with fuel, is there a way to purge it?” “No.” I then explained the numbers I had made and we went through them together.

Next step: check the fuel indicator of the plane… ~3/4… or about 80L, with the reserve deposit empty. We would be just within the limit!

We then proceeded with the preparation of the route, the pre-flight check, etc., and had good time with the flight (see report of the experience by my sister, in Spanish).

From this experience I learned a take away for future flights: when finishing your flight, it is normal etiquette towards the next pilot to refuel the aircraft if you see that the deposit is almost empty, however, it can be counter productive to fill it up completely if the next pilot is going to fly with passengers and close to the MTOW. I would then suggest that it is better to just fill it up to the volume where you know that the next pilot can have all choices open. For our DR-44 that would be filling it up to 3/4 of the main deposit (leaving reserve empty) (2). If the next pilot wants to travel along to a far distance needing more fuel he can always fill up more litres. This target weight will be different for each aircraft.

(1) See here another post I wrote two years ago about weight and balance calculations in the same plane model.

(2) Bear in mind that I found the airplane with precisely ~80L: coincidence or the previous pilot had come to the same conclusion at some point?

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“A bird in the hand is worth two in the bush” (speech)

Thanks to the drive of some individuals (Sarah, EduardoDominique) a new Toastmasters corporate club (1) is being created within Airbus in Toulouse, where I work.

I joined Toastmasters in 2007 when I lived in Madrid and I have written often about Toastmasters in this blog, however I had become inactive in the last couple of years. This new initiative is very convenient and thanks to it I am engaging myself again in the association.

Today, I gave again a prepared speech in Toastmasters (2). In this post I just wanted to share it. Find it here, “A bird in the hand is worth two in the bush”, and below:

A bird in the hand is worth two in the bush

The topic of the speech is known for the reader of this blog: impact of delays in aircraft development projects seen as investment projects, the time value of money, discounting cash flows, break even, etc.

The feedback that I got: It was well received, especially the introduction, the interaction with the audience, the structure and how the topic was introduced and the main points called back in the end. However, I lost some individuals with the last slide, which needed some more explanation. I should have simplified the graphic. Some demanded more pauses and better vocalization.

(1) Up to now it is a prospect Toastmasters club.

(2) Project #1 of the “Speeches by Management” advanced manual: “The briefing”.

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Filed under Aerospace & Defence, Investing, Toastmasters