loading Loading please wait....
Login

If you are a registered, please log in. If not, please click here to register.

Aircraft Comparative Analysis - Gulfstream III

In this month’s Aircraft Comparative Analysis we provide information on a selection of pre-owned business jets in the $2.5-6.5m range for the purpose of valuing the Gulfstream GIII. We’ll consider the usual productivity parameters - payload/range- speed and cabin size - and cover current and future market values. The field in this study includes Dassault’s Falcon 900 and Bombardier’s Challenger CL601-1A and CL601-3A.

BRIEF HISTORY
The Gulfstream GIII’s first flight occurred in 1979. Ultimately- the GIII is a GII stretched by 24 inches with a modified wing and nosecone. The modified wing was derived from that of the GII- with a nine-foot extension that added 746 gallons of fuel- and incorporated winglets and leading edge extensions.

These modifications provided a higher gross weight that resulted in greater speed and longer-range using the same two Rolls-Royce Spey 511-8 engines as the GII.

The GIII can be RVSM certified. There were 202 Gulfstream GIII aircraft built- and 195 currently remain in service.

PAYLOAD AND RANGE
The data contained in Table A (overleaf) is published in the B&CA (May 2011 issue)- but is also sourced from Conklin & de Decker. As we mentioned in past articles- a potential operator should focus on payload capability as a key factor. The Gulfstream GIII ‘Available payload with Maximum Fuel’ at 2-610lbs has the highest payload capability in this field of study.

CABIN VOLUME
According to Conklin & de Decker- the cabin volume of the GIII is 1-345 cubic feet - which is larger than that of a Falcon 900 (1-264 cubic feet) by 6.4% and 30% larger than both the Challenger 601-1A and -3A aircraft (1-035 cubic feet) - see Chart A (left).

POWERPLANT DETAILS
As mentioned previously- the GIII aircraft is powered by two Rolls-Royce Spey 511-8 engines- each offering 11-250 lbst. The Falcon 900 aircraft utilizes three Honeywell TFE 731-5AR-1C engines. The Challenger CL601- 1A and -3A have two General Electric CF34- 1A and CF34-3A engines respectively.

Using data published in the May 2011 B&CA Planning and Purchasing Handbook and the August 2011 B&CA Operations Planning Guide we will compare our aircraft. Jet A fuel cost used from our source publications was $6.04 per gallon at press time for the August 2011 edition - so for the sake of comparison we’ll chart the numbers as published.

Note: The fuel price used from this source does not represent an average fuel price for the year.

Table B (left)- as sourced from Aircraft Cost Calculator (ACC)- shows the fuel usage by each aircraft model in this field of study. One of the unique benefits of using ACC is to quickly analyze- evaluate and customize by inserting your own numbers that will provide accurate operating numbers for your own aircraft and/or flight department.

The Gulfstream GIII at 550 gallons per hour (GPH) leads the field with the highest fuel usage- followed by the Falcon 900 aircraft at 335 gallons per hour. The Challenger 601-1A/3A are the most frugal on the list with 329 gallons per hour.

COST PER MILE COMPARISONS
Chart B (left) details “Cost per Mile” comparing the GIII to its competition factoring direct costs and with all aircraft flying a 1-000nm mission with an 800 pound (four passengers) payload. The GIII at $11.69 cost per mile has a significantly higher cost compared to the rest of the field.

TOTAL VARIABLE COST COMPARISONS
The ‘Total Variable Cost’- illustrated in Chart C (top- right)- is defined as the cost of Fuel Expense- Maintenance Labor Expense- Scheduled Parts Expense and Miscellaneous trip expense. The total variable cost for the GIII - at $4-973 - is significantly more expensive to operate compared to the rest of the field.

PRODUCTIVITY COMPARISONS
The points in Chart D (middle right) center on the same group of aircraft. Pricing used in the vertical axis is as published in Vref. The productivity index requires further discussion in that the factors used can be somewhat arbitrary.

Productivity can be defined (and it is here) as the multiple of three factors:
1. Range with full payload and available fuel;
2. The long-range cruise speed flown to achieve that range;
3. The cabin volume available for passengers and amenities.

The result is a very large number so for the purpose of charting- each result is divided by one billion. The examples plotted are confined to the aircraft in this study. A computed curve fit on this plot would not be very tight- but when all business jet aircraft are considered the “r” squared factor would equal a number above 0.9. Others may choose different parameters- but serious business aircraft buyers are usually impressed with Price- Range- Speed and Cabin Size.

After consideration of the Price- Range- Speed and Cabin Size we can conclude that the GIII as shown in the productivity index is highly productive within its comparative field. We also included the plotting on this chart of the Gulfstream GIV to illustrate the continued improvements made to the Gulfstream product line.

In summary- by direct comparison to the field in this study- the GIII has the largest cabin volume; costs significantly more to operate per mile and has the highest variable cost of the competitors in this field. In addition- the GIII offers the fastest speed (TAS) at 478 kts- the longest range with maximum payload- and sells at a competitive price.

Table C (right) contains the relative retail prices from Vref for each aircraft in the comparative field. The number of aircraft in-operation- percentage “For Sale”- and the number “Sold” over the past 12 months are from JETNET. As shown- the GIII has averaged 2.8 aircraft sold per month over the past 12 months.

LOCATION BY COUNTRY
The information shown in Table D (overleaf) is compiled from JETNET Evolution and STAR reporting systems- and can be valuable for dealer/broker repeat business. The majority (77%) of the GIII fleet resides in the United States. Table D outlines the ‘TOP 5’ Countries where a combined 85% of the GIII aircraft are located.

The only country in Europe with a Gulfstream GIII is Ireland- and it is counted in the ‘Other’ category of Table D. Certainly contributing to the lack of GIII aircraft in Europe is an EASA requirement that a Hush-kit be installed before operation can commence in most of the major airports within Europe.

SUMMARY
In the preceding paragraphs we have briefly covered several of the attributes that business aircraft operators value. There are other qualities beyond the scope of this article to consider- such as airport performance- terminal area performance- and time to climb performance. The GIII performs well in these areas too.

The Gulfstream GIII fares well- so those operators in the market should find the preceding comparison of value. Our expectations are that the GIII will continue to do well in the pre-owned market.

For more information: Michael Chase is president of Chase & Associates- and can be contacted at 1628 Snowmass Place- Lewisville- TX 75077; Tel: 214-226-9882; Web: www.mdchase.com

Do you have any questions or opinions on the above topic? Get them answered/published in World Aircraft Sales Magazine. Email feedback to: editorial@avbuyer.com


Related Articles