Comment by Mark Jones Jr. on Aerodynamics of Flight Control Surfaces
Lift is not linear. Especially once it reaches the stall angle of attack.
View ArticleComment by Mark Jones Jr. on Who was the first flight test engineer?
Presumably is not an answer. And I have references with earlier answers.
View ArticleComment by Mark Jones Jr. on Rotor Tip Speed vs Forward Airspeed - IAS or TAS?
Airplanes stall at the same indicated airspeed, not true airspeed.
View ArticleComment by Mark Jones Jr. on Can I go into clouds if I got IFR clearance?...
Without an ATC clearance, you are under Visual Flight Rules (VFR). Therefore you may not enter clouds, as defined in the 14 CFR: gleim.com/aviation/faraim/?leafNum=91.155.
View ArticleComment by Mark Jones Jr. on How can ice form in an OAT of +20°?
Please provide a reference that we can crosscheck to validate that EASA actually says this, because this seems like an error.
View ArticleComment by Mark Jones Jr. on What are the chances of a fresh pilot school...
There are many pilot forums online which are a better place to ask this kind of question.
View ArticleComment by Mark Jones Jr. on Why did the Concorde have a prohibition on...
Seems reasonable. Do you have a reference?
View ArticleComment by Mark Jones Jr. on Why did the Concorde have a prohibition on...
Though I think your intent is correct, the actual statement is patently false: "manufacturers and airline operators prohibit configuration changes at low altitude." Gear and flap retraction both occur...
View ArticleComment by Mark Jones Jr. on Are there Hybrid Electric-Combustion Turbine...
Your answer could be improved with additional supporting information. Please [edit] to add further details, such as citations or documentation, so that others can confirm that your answer is correct....
View ArticleComment by Mark Jones Jr. on When did the color orange enter flight test?
Thanks. I wrote those articles.
View ArticleComment by Mark Jones Jr. on Does climbing or descending affect the rate of...
"At the extreme limit case where the flight path truly is aimed vertically downward, the wing is generating no lift." This is false.
View ArticleComment by Mark Jones Jr. on Will air in a shockwave flow outwards?
The physics of light don't apply directly to aerodynamics. I don't think mentioning them is helpful here. Additionally, the shockwave is a nonlinear boundary in wave behavior. So almost everything you...
View ArticleComment by Mark Jones Jr. on Will air in a shockwave flow outwards?
One of the fundamental principles of aerodynamics is that particles of air remain in their streamline. This is not strictly true in turbulent error where air is mixed. But it is an important aspect of...
View ArticleAnswer by Mark Jones Jr. for When should I start turning in this circling...
The FAA instrument flying handbook discusses techniques and the procedures by which circling approaches must be conducted.1You must remain within the protected area or circling radii, but as soon as...
View ArticleAnswer by Mark Jones Jr. for Why is there a helicopter visibility reduction...
Helicopters may operate under special VFR when in flight visibility is less than 1 SM. Therefore, the approach can be flown at lower visibility than that published on the approach plate. However, the...
View ArticleAnswer by Mark Jones Jr. for What is the incidence angle of a propeller in...
According to various scholars, the Wright brothers were referring to "angle of attack" when they used the term "incidence." They actually published an article by the same title, so the fact is...
View ArticleAnswer by Mark Jones Jr. for How to become Hybrid airship Pilot?
Yes, they are different. A hybrid airship has the characteristics of an airship, but it also generates lift based on its aerodynamic shape (like a powered aircraft wing).The FAA defines an airship as...
View ArticleAnswer by Mark Jones Jr. for Why are airports like Roswell and Fresno so...
The FAA does regulate "where" flight test can be performed, in 14 CFR Part 91, which says:§91.305 Flight test areas.No person may flight test an aircraft except over open water, or sparsely populated...
View ArticleAnswer by Mark Jones Jr. for What is the speed during push-back?
There is no regulatory guidance on how fast (or how slow) an aircraft must move during the pushback. Furthermore, there are many opinions (see below) on how fast an airplane moves during pushback.If...
View ArticleAnswer by Mark Jones Jr. for How much safer does painting prop tips make a...
Painting the propeller tip is required by current regulations, most of which evolved from earlier variants of policies and procedures in each service or organization. The FAA's guidance says:For safety...
View ArticleAnswer by Mark Jones Jr. for Were there any test flying incidents during...
During the early development flight tests of the Challenger, an aircraft was trapped in a deep stall. Two crew members bailed out, but the final crew member did not survive the bail...
View ArticleAnswer by Mark Jones Jr. for How are fuel tanks tested and certified?
As an example of what ground testing may be conducted, reference this Test Report from the FAA.In this test, the fuel tanks were inerted with the On Board Inert Gas Generation System (OBIGGS). Various...
View ArticleAnswer by Mark Jones Jr. for Can I go into clouds if I got IFR clearance?...
Yes. First note that takeoff from any IFR qualified airport will allow for takeoff and avoidance of obstacles by traditional TERPS methods. Therefore, the type of airspace has no effect on IFR obstacle...
View ArticleAnswer by Mark Jones Jr. for Which airplane types never crashed?
A comprehensive answer to your question would be very difficult. The Honda Jet has never crashed. The Boeing 787 has never crashed. The A380 has never crashed, but both appear in safety databases based...
View ArticleAnswer by Mark Jones Jr. for Why are FDRs and CVRs still two separate...
The Cockpit Voice Recorder and Flight Data Recorder are the same unit on many modern aircraft and are widely available at vendors such as this resale outlet and direct from vendors like Universal.
View ArticleAnswer by Mark Jones Jr. for How are METARs published?
Though this reference is second-hand information, the author suggests that the National Weather Service explains why some reporting stations do not get collated or transmitted by agencies like the FAA...
View ArticleWhat experimental techniques should one employ during cruise flight to...
Theory demonstrates that one ought to increase speed in an headwind, and decrease speed in a tailwind to achieve maximum range. A lengthy discussion on the theoretical solution was answered, though not...
View ArticleThroughout aviation history, what airships were metal clad?
Throughout aviation history, what airships were built with metal skin instead of fabric or other material?
View ArticleAnswer by Mark Jones Jr. for Is there any common research model for...
According to NASA here:This test case is an aircraft concept previously used as an optional case (LM1021) in the 1st Sonic Boom Prediction Workshop. This configuration is described in the following...
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Answer by Mark Jones Jr. for Do the FACs compute every speed value shown on...
Yes. Kind of--the air data computers do some of the computations and display those based on hard coded limits. For example, an ADC will compute current AOA and may have the AOA limits hard coded...
View ArticleAnswer by Mark Jones Jr. for What does the extending the flaps do (or any...
According to the FAA, lowering or extending flaps allows one to increase drag without an increase in speed. This increases descent rate for a given speed. One must be careful to consider what factors...
View ArticleWhat was the first control room--used for flight test--established in...
The control room for space missions in Houston is probably the best, most widely known example of a control room. It is an operations center used in support and execution of flight and space...
View ArticleWhy do we say certain things three times (e.g., "Mayday, Mayday, Mayday"),...
Repetition is a key characteristic of communication in the control tower, cockpit, and control room. Some phrases, like "Mayday" get repeated. The speaker says the same thing three times. We know this...
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Answer by Mark Jones Jr. for Why does the F-15 have a swept-back trailing...
The F-15 wingtip is a "raked" tip configuration, which increases lift and decreases drag.1[]2This is the design decided by the USAF after discovery of several design deficiencies during initial flight...
View ArticleAnswer by Mark Jones Jr. for Are there any aircraft with retractable vortex...
Bell Textron filed a patent for retractable vortex generators in 2006. The patent is here.Boeing also filed a patent for vortex generators that extend simultaneously with a leading edge slat here.
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Answer by Mark Jones Jr. for NEXRAD—why is it 2D?
Data about the height of precipitation would be useful in real-time avoidance of weather phenomena. In fact, this information is provided by NEXRAD and is known as "echo tops." Echo tops also appear in...
View ArticleAnswer by Mark Jones Jr. for How do Flight Test Engineers plan and execute...
Three main factors influence the flow of a flight test sortie: data requirements, test point priority and flight efficiency. For example, consider a test sortie that requires evaluation of stall...
View ArticleAnswer by Mark Jones Jr. for Has any Cessna Denali ever flown yet...?
Latest news says first flight is planned in 2020, due to engine testing delays. https://www.ainonline.com/aviation-news/business-aviation/2019-10-21/cessna-denali-first-flight-delayed-2020With five...
View ArticleAnswer by Mark Jones Jr. for Derivation of the Takeoff equation
We want to reduce (or simplify) equation 2, to get get dV/dt by itself, so we multiply both sides by g/W. On the right hand side, this reduces to dV/dt.On the left hand side it reduces to what is given...
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Who was the first flight test engineer?
The discipline of Flight Test Engineering has existed since at least 1903, but when did engineers identify their work, distinguish their work from other disciplines, under terms that would mark it as...
View ArticleAnswer by Mark Jones Jr. for Why was the minimum turbulence intensity that...
According to the FAA, "The final PSD continuous turbulence criteria were based on those studies and were codified in Appendix G to part 25 in 1980."This matches the timeline you suggest, but the...
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Answer by Mark Jones Jr. for How can ice form in an OAT of +20°?
EASA produced a pamphlet for GA Piston Engine icing. It states:Carb icing is not restricted to cold weather. It will occur on warmdays if humidity is high, especially at low power settings. Flighttests...
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When did the color orange enter flight test?
When did the color orange enter flight test? As early as the Bell X-1, pictured here, aircraft were painted orange to enhance visibility. Later, in 1959, a study was conducted that suggested the...
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