Increase engine efficiency and how? Pratt and Whitney to demonstrate the concept of "rotating engine detonation"

Pratt and Whitney, in collaboration with Raytheon Missiles & Defence and Raytheon Technologies Research Center, has secured a contract with the United States Air Force (USAF) to develop a ground test demonstration of a rotating engine detonation concept.

Representative | Defense Here

The value of the contract is undisclosed as of yet and the collaboration is aimed at developing an engine capable of supporting higher-Mach flight speeds.

Pratt & Whitney’s Gatorworks was able to complete initial concept development well ahead of schedule, and we will continue leveraging our digital and agile capabilities to accelerate progress on this programsays Dave Stagney, director of Gatorworks, Pratt’s prototyping arm

So, what is the concept all about?

Rotating detonation engine (RDE)

A conventional jet engine offsets massive spike(s) in temperature and pressure by allowing the volume of gas to expand as it’s sprayed or injected into the combustor. The resulting stream of combustion gases passes through the engine, spinning turbine blades as it exists.

Conventional jet engine | Wikimedia Commons

The entire working of an RDE revolves around a detonation wave that travels around a circular channel (annulus). Fuel and oxidizer are injected normally through small holes or slits.

An igniter is used to initiate the detonation in the fuel-oxidizer mixture. This releases the energy necessary to sustain the detonation. The combustion products expand out of the channel and are pushed out of the channel by the incoming fuel and oxidizer.

"A rotating detonation engine operates via a continuous detonation wave that propagates around the inside of a cylindrical combustor. Air and natural gas propellant (blue) are introduced continuously through the inlet and react across the detonation wave that is moving perpendicular to the incoming propellant. High-temperature, high-pressure products behind the detonation wave expand and exhaust out (top) to drive a turbine or generate thrust. Once the process begins, it self-sustains as long as the inlet propellant is flowing". Credit: Staff research, Aerojet Rocketdyne

It is to be noted though, that the design of the combustor would be radically different- one that would release energy in a rapid, continuous succession of detonations set off by shockwaves rotating inside a cylindrical combustor.

Technically speaking, an RDE should slash specific fuel consumption by about 5% compared to a conventional engine. A rotating detonation engine would slash specific fuel consumption further.

Given the need for this critical engine technology, the Raytheon Technologies team will utilize its advanced resources and expertise to meet the technical objectives in an expeditious fashion. The engine is being designed to fly at higher Mach speeds which will enable and broaden future vehicle designs and applications and will be a key element of Pratt & Whitney’s high-speed engine portfolio to meet future customer requirementssays Gatorworks

Reportedly, technology is been increasingly seen as important for the future development of hypersonic vehicles.

SOURCE(s)

COVER: Asia Pacific Defence Reporter

The Iran Aviation Industries Organization (IAIO), also known as the Aerospace Industries Organization, is an Iranian, state-owned organization, overseeing the civil & military aviation industry of Iran.

According to a report by Touraj Dehqani Zanganeh- head of the country’s Civil Aviation Organization, the country now might be heading towards building a commercial aircraft of its own, with a capacity of about 100 passengers.

Representative | Wikimedia Commons

The US has often, and categorically accused Iran of unveiling aircraft models that are supposedly mock-ups or modified versions of outdated planes. Due to US sanctions, Iranian experts have had to rely on in-house capabilities to cater to its defence needs. The imposed sanctions are also one of the reasons why Iranian airlines are often found operating older aircraft models- like the Airbus A300, Fokker 100s, MD-80S and other vintage models.

Hassan Rouhani, the Iranian president is seen waving to a fighter pilot before an inauguration ceremony of an aircraft, Iran, on August 21, 2018, | Representative | Caspian News

Apparently, the ministry plans to manufacture civil aircraft as the government looks to expand its partnership with private players.

In the field of aerospace and automotive industries, we (Iran’s Defense Ministry), have tried to help the prosperity of these two industries with technological assistance and meeting the needs of automakersDeputy Defense Minister for Parliamentary Affairs Brigadier General Reza Talaei-Nik said at a press conference during a technological exhibition

The Iran -140, loosely based on the An-140 | Representative | FlightGlobal

Coincidentally, the news of the development of a new passenger aircraft comes as the Iranian fleet faces an acute shortage of new aircraft.

According to Dehqani, there exists a Memorandum of Understanding (MoU)  between Iran’s Civil Aviation Organization, Ministry of Defense, and the Transport and Urban Development Ministry.

We have planned to build 70- and 100-seat aircraft inside the country, and in this regard, we signed a memorandum of understanding (MOU) with the Ministry of Defense to be able to use the country’s existing military capabilities for the construction of commercial aircraftTouraj Dehqani Zanganeh

Apparently, there are numerous knowledge-based companies in the country-Mapna and other potential companies that are currently building gas turbines- Dehqani further added.

Nevertheless, the country still produces fighter jets like the Kowsar and Qaher-313 although most of them appear to be heavily based on vintage US airframes.

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COVER: v1Images Aviation Media

Turkey has an ageing Air Force with most of its old F-16s either requiring repairs or an immediate update. With Greece, its arch-nemesis buying the more advanced Rafale, the hierarchy of power seems to have shifted in the region.

Representative | Daily Sabah

Considering the scenario, and recognizing Turkey's need to upgrade its fleet with an advanced aircraft, the CEO of Turkish Aerospace recently announced that it would be collaborating with Pakistan to develop what could be dubbed as the first-ever fighter jet manufactured in the Islamic world.

A brief history

The fighter aviation market has been dominated by Russia and the Western powers for decades now with US and USSR emerging as the undisputed leaders in this niche since the late 1970s. China has been playing catch-up and is the first country besides the US to build a 5th gen fighter craft and introduce it into service.

Analysts and officials from the Islamic states of  Iran, Pakistan and Turkey have expressed concern over the fact that the Islamic states always have had to rely on foreign aircraft for their inventories.

Representative | BETSOL

Even today, the participation of a country in military aviation is set as a benchmark indicating superior battle prowess and state power.

Here are some of the major fighter programs pursued by the Muslim states, some successful and some who bit the dust.

1. Egyptian Helwan Ha-300 Fighter Prototype

The Ha-300 was the capable jet fighter ever designed by a Muslim state and gave a good run for money to other third-generation fighter jets at the time. This supersonic fighter reached an advanced prototype stage in the mid-1960s and was touted to have been built as a replacement for the Soviet MiG-21 and MiG-19 second-generation jets in the Egyptian Air Force and friendly Arab states such as Syria, Iraq and Algeria.

designer.home.xs4all.nl

2. Kowsar 

The first Iranian fighter jet to enter serial production, Kowsar was a lightweight Gen 4 craft thought to be at par with the American F-20 Tigershark, and like the Tigershark, it is closely based on the F-5E Tiger II third-generation jet for which Iran was a leading client. Although claimed to be an indigenous production by Iran, eyebrows have been raised on those claims, especially since it could rely on North Korean or Chinese technologies for electronic warfare, avionics or engines as Iran’s defence sector has traditionally relied very heavily on technology transfers from these two states.

Military Watch Magazine

3. Qaher-313

Yet another product of Iran, and this was the only model to have reached the prototype stage which was not directly derived from the American F-5. Again, it is highly likely that the Qaher would have imbibed many technologies from the Kowsar fighter which entered service in 2018, and the stealth fighter’s engines could have been derived from those of the Kowsar but enlarged to support a heavier airframe.

The National Interest

The Turkey-Pakistan collaboration- TF-X

Turkey is now planning to jointly develop fighter crafts and missiles with Pakistan, which reportedly, might also make it easier for the country to get access to valuable Chinese military technology.

Representative | Wikiwand

Having been launched in December 2010 under the TF-X ( Turkish Fighter- Experimental) program, it is touted to be a stealthy twin-engine fighter jet comparable to the F-35

Recently, a full-scale mock-up was unveiled at the Singapore Air Show, in what can be described as the first such move in Asia.

This is a fifth-generation fighter aircraft on which Pakistan and Turkey are now cooperatingAir Vice-Marshal Dr Rizwan Riaz, Pro-Rector Research, Innovation & Commercialisation (RIC) at National University of Science and Technology (NUST)

Reportedly, the prototype is planned for 2023 while its maiden flight is scheduled for 2026.

Defence Turkey, a Turkish defence website, has estimated it would cost around $21 billion to develop and produce the TF-X fighter, including $7.3 billion for development alone.

SOURCE(s)

COVER: Defence Turkey Magazine

The normal pull of 1 G force is what keeps us from floating away into space. The extreme acceleration of a fighter aircraft exposes the pilot to massive G forces, which could be five times as much as normal. To put things into perspective, a pilot who weighs 160 pounds at one G would weigh 960 pounds at six Gs.

Representative | FindLight

Imagine having to attend nature's call while being exposed to such extreme G forces and at 30,000 feet. Sure doesn't sound fun. And it's even more cumbersome than you think.

If the flying sortie is of short duration, the pilot can sometimes hold it back in-although it can be hazardous to kidney health.

With air refuelling allowing for longer flights now, "holding back" is just not an option.

So, how do they manage the task?

Historically

Apparently, the problem of relieving a pilot's bladder while flying fighter jets has been around for decades. Initially, pilots resorted to "tactical dehydration" by avoiding water during the mission(s) to prevent visits to the lavatory.

Mission times vary greatly. An air-to-air dogfighting training mission can be less than an hour, while a mission   that involves aerial refuelling could last 6 plus hours. For longer missions, it’s common not to drink too much inflight but that can lead of course to dehydration and possible diminished operational effectiveness.Jeff Devlin from Skyborne Airline Academy-a former US Marine Corps F-18 fighter pilot

Jeff Devlin (right) | Source

Dehydration can cause undesirable effects like headaches, reduced endurance and G-force tolerance- all of which are detrimental for accurate flying.

Some of the methods that have been developed are:

Piddle Packs: It is essentially a plastic bag but made of a much thicker ply-about the size of a hard covered novel. Inside this bag is a powdered substance. The bag has a built in metal twist-tie to secure the bag after its been opened. For this of course, the pilot has to unstrap and unzip, which has caused a few accidents in the past. The powder turn into a gel as urine saturates it- turning it into a non-spilling substance which can then be stored away. Throughout the entire routine, the jet is either put in an altitude hold (auto pilot), or just trimmed up real well to keep the jet from nosing over/up when you release the controls. The whole process is completed in under a minute.

Piddle pack | US Department of Defense)

These packs are also commonly used for ocean crossings that take 10 plus hoursJeff Devlin

The Aircrew Mission Extender Device (AMXD)

Adopted by the U.S. Air Force as a replacement to piddle packs, this apparatus is a wearable device, that detects urine and flushes it into a bag for storage.

Once the AMXDmax automatically detects urine, it pumps it into a collection bag and because urine is nasty, sensors detect the urine within a second and rapidly pump it into a 1.7 quart (6.8 cups) collection bag. In comparison to piddle bags, pilots now don't have to undress in the cockpit- technically releasing the bladder is all the pilot does. The device looks like a black pair of tight-fitting boxer shorts concealing either a cup or a pad.

Representative | The Drive

Additionally, it comes in two different versions for men and women respectively.

For women | Representative | Source

For men | Representative | Source

The new devices are hands-free, battery operated and worn underneath uniformsAccording to Military.com

Ongoing research and development

Reportedly, Royal Air Force (RAF) has been collaborating with the US Airforce in the development of the Omni Gen. 3 Skydrate which is an upgrade to the existing Advance Mission Extender Device (AMXD).

Representative | Task and Purpose

The RAF has been heavily involved in research and development of a variety of devices and have been instrumental in offering feedback to improve systems with the RAF Centre for Aviation Medicine (RAF CAM) being a world leader in this area.A senior Royal Air Force source said 

As per reports, Skydrate has been modified to improve the design and effectiveness of the pad after feedback from female pilots and is now available for both men and women.

US aircrew is set to receive Skydrate by spring of this year.

SOURCE(s)

COVER: Air Force Times

Jet fuel prices on Tuesday, March 1 were increased by 3.3% to all-time high levels across the country, in step with international oil prices surging to over seven-year-high.

This is the fifth hike in jet fuel or Aviation Turbine Fuel (ATF) prices this year following an unrelenting rise in global oil prices, but petrol and diesel prices remained unchanged for a record 116th day in a row, coinciding with electioneering to elect new governments in states like Uttar Pradesh and Punjab.

In five hikes beginning January 1, ATF prices have been increased by INR 19,508.25 per kl or 26.35%.

ATF price was hiked by INR 3,010.87 per kilolitre or 3.22% to INR 93,530.66 per kl in the national capital, according to a price notification of state-owned fuel retailers. Jet fuel, which makes up for almost 40% of the running cost of an airline, has this year surged to new highs.

The previous peak of INR 71,028.26 per kl was recorded in August 2008 when international crude oil prices touched USD 147 per barrel. Brent crude oil on Tuesday, March 1 was trading above USD 100 per barrel.

ATF prices have increased every fortnight since the start of 2022. In five hikes beginning January 1, ATF prices have been increased by INR 19,508.25 per kl or 26.35%.

Aviation fuel prices increased by 3.3% to new all-time highs

These hikes in the rate came on the back of two rounds of price cuts seen in December that reflected a drop in international oil prices during the second half of November and mid-December. Thereafter, international rates have firmed up, leading to the hike in ATF prices.

ATF prices had last peaked at INR 80,835.04 per kl in mid-November 2021 before it was cut on December 1 and 15 by a total of INR 6,812.25 per kl or 8.4%.

Jet fuel prices are revised on the 1st and 16th of every month based on the average price of the international benchmark in the preceding fortnight.

Brent crude oil on Tuesday, March 1 was trading above USD 100 per barrel.

This is despite a wild swing in international oil prices. Brent crude oil, the best-known international benchmark, was at USD 82.74 per barrel on November 5, 2021, before it started to fall and touched USD 68.87 a barrel on December 1.

Prices have climbed to over USD 105 per barrel last week following the Russia-Ukraine crisis and is now trading at USD 100.99, well above the peak of USD 86.40 touched on October 26, 2021, which had led to petrol and diesel prices spiking to an all-time high.

Civil Aviation Minister Jyotiraditya Scindia on Monday, February 28 said that 23 states have slashed value-added tax (VAT) on jet fuel, also called aviation turbine fuel (ATF), and he is working with other states to lower tax. He said he would not rest until the burden of higher jet fuel becomes lower.

Getting started

A Circadian Rhythm is any biological phenomenon that involves self-sustained oscillation during 24 hours, caused by the earth's rotation. Everyone in the world has an inbuilt "body clock" and it works much, in the same way, a finely tuned watch-making sure every system of the body works in unison to keep the body in homeostasis ( maintenance of the internal processes within tolerable limits).

Representative | Airport Parking Reservations.com

There are clearly recognizable patterns of brain-wave activity, hormone production, cell regeneration, and other biological activities linked to each individual's daily cycle.

How does it work and what makes it relevant?

The "suprachiasmatic nuclei" located within our brain, sort of act like a pacemaker and regulate the firing of nerve cells that seemingly control our circadian rhythm. Although it can't be precisely said how exactly this part of the brain "keeps time", it is scientifically established that it does rely on "outside" influences to keep the rhythm running.

Representative | Blendspace

Circadian rhythm is impacted by lightness and darkness received throughout the day. Most people’s clocks are naturally set to be the most alert in the mornings and late afternoon. For those who work long hours or graveyard shifts, there can be long term repercussions from ignoring the body’s natural cycle.

Circadian Rhythm Disruption (CRD)

Every time our normal 24-hour period Circadian Rhythm is altered or interrupted, it is bound to have physiological and behavioural impacts- resulting in what is known as "Circadian Rhythm Disruption".

Representative | Shift Workers Health

CRD is more apparent in shift work as now the shift timings are often at loggerheads with our internal body clock. This can result in a wide range of highly documented issues ranging from performance issues to accident and health problems.

Disruption of the biological clock and its impact on pilots

Flight and cabin crews operating on long-haul routes often have to cross multiple time zones, sometimes within the same day. The rapid changes in time zones often disrupt the natural biological cycle and result in what is called a "Jet Lag". Yes, jet lag is also a Circadian Rhythm Disruption. Of all the stressors in aviation, Jet Lag is what seems to hit the hardest.

Representative | Shall We?

The effects of jet lag include health problems such as fatigue, irritability, reduced mental acuity, slow reaction time, mood swings and digestive issue. The decreased cognitive abilities can affect the performance of a pilot flying, on whose hands the entire safety of the flight operation rests.

Representative | The pilot who explores

Scientifically, the effects of jet lag seem to be more prominent when flying from west to east as it becomes difficult for the body to adjust to "losing time" when we journey east as opposed to flying west from the east where we "gain time".

CRD as affecting pilot skills:

Increased reaction time to sequential tasks that require time synchronizationImpaired memoryEmotional irritability, amongst many others

How can the pilots counter these inevitable effects?

It is a given that reduced sleep impairs cognitive performance, thereby making red-eye pilots more susceptible to human error incidents. Fortunately, there are prediction models in place that dictate the pilots when to eat, exercise and sleep based on their working schedule so they can be as alert as possible and get everyone to their destination safely.

Red-Eye flights | Representative | Conde Nast Traveler

Additionally. airliners are now employing new sleep monitoring devices that will help accurately gauge when a pilot may be getting overworked and too fatigued to fly safely.

How do you restore your bio clock and recover?

Catch the sun: Exposing yourselves to sunlight has been scientifically proven to be beneficial in helping reset circadian rhythms. Additionally, this light therapy has a direct and positive effect by increasing brain serotonin levels.

Representative | Culture Trip

Be active: Taking a nap on arrival is the worst you can do as it sets the bio clock back to your home time. It is equally important to blend in with the local time(s) for all activities of the day.

Countering CRD while on duty

Avoid pilot adaptation to a local circadian rhythm following trans-meridian flights with short layoversAlternate trans-meridian flights with intra-meridian flights which will enable a smooth transition to normal circadian rhythmsAvoid night flights following a trans-meridian flightUse caffeine strategically to counter circadian rhythm sleepinessAvoid naps longer than 30 minutes as they involve "deep" sleep

Circadian Rhythm Disruption is also touted to lead to extreme chronic fatigue in the cockpit, the effects of which could just as debilitating as drugs and alcohol.

Nevertheless, pilots are trained extensively well and are very tuned in to their personal needs during a flight and hence you’re in highly qualified hands.

SOURCE(s)

COVER: Fodors Travel Guide